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Post-transplant lymphoproliferative disease (PTLD) is defined as a lymphoma that occurs after solid-organ or hematopoietic stem-cell transplantation (HSCT), caused by immunosuppression and Epstein-Barr virus (EBV) reactivation. It is an important post-transplant complication that can be fatal. After HSCT, most PTLD occurs within 2 years. Recent evidence suggests that tyrosine kinase inhibitors (TKIs) are expected to be effective maintenance therapy after HSCT for Philadelphia chromosome-positive leukemia. However, it is unclear whether the use of TKIs might pose a risk of developing PTLD after HSCT. We present the first case of late-onset PTLD during dasatinib treatment, which occurred 10 years after umbilical cord blood transplantation (CBT). A 59-year-old man who received CBT for chronic myeloid leukemia blast phase needed long-term dasatinib therapy for molecular relapse. Ten years after CBT, he developed diffuse-large B-cell lymphoma (DLBCL). We observed chimerism of the DLBCL sample, which indicated complete donor type and EBV-DNA, and the patient was diagnosed with PTLD. Because of treatment resistance, he died 6 months after PTLD onset. Although he received no long-term administration of immunosuppressive agents, he received long-term dasatinib treatment, which suggests that prolonged dasatinib use after CBT caused EBV reactivation and led to PTLD. Our case suggests that the potential contribution of molecular-targeted agents after HSCT to the development of PTLD should be carefully considered.

Essential thrombocythemia (ET) mainly affects the elderly, but can also develop in women of childbearing age. The risk of miscarriage and other complications during pregnancy in ET patients are reported to be higher than that compared to the general population. Therefore, management of pregnancy in ET patients requires special considerations. Several groups recommend interferon (IFN) therapy for ET patients with high-risk pregnancies, but currently no guidelines are available in Japan. We report the outcomes of nine ET patients with ten consecutive high-risk pregnancies. All patients were successfully managed with IFN-α during their pregnancies. All patients also received aspirin and switched to unfractionated heparin around 36 weeks of gestation. As for the seven pregnancies in which IFN-α was started after detection of pregnancy, median platelet counts decreased from 910 to 573 × 109/L after 2 months of IFN-α therapy, and median platelet counts at the time of delivery for all ten pregnancies was 361 × 109/L. All patients gave birth to healthy children. IFN-α was well tolerated, safe, and effective as a cytoreductive therapy for all patients. Although evidence is limited and the use of IFN is not approved in Japan, we suggest considering IFN therapy for high-risk ET pregnancies.

We conducted a large-scale, nationwide retrospective study of Japanese patients who were diagnosed with essential thrombocythemia based on the diagnostic criteria in the World Health Organization classification. We investigated clinical characteristics, survival rates, and the incidence of thrombohemorrhagic events as well as risk factors for these events. A total of 1152 patients were analyzed in the present study. Median age at diagnosis was 65 years, the median platelet count was 832 × 109/L, and the positive mutation rates of JAK2V617F, CALR, and MPL were 62.8, 25.1, and 4.1%, respectively. Compared with European and American patients, Japanese patients were more likely to have cardiovascular risk factors and less likely to have systemic symptoms including palpable splenomegaly. Thrombocytosis was identified as a risk factor for hemorrhagic events and prognosis, but not for thrombotic events. The prognostic factors and risk classifications reported in Europe and the United States were generally applicable to Japanese patients. Regarding transformations, secondary myelofibrosis progressed in a time-dependent manner, but progression to acute leukemia was low in "true" ET patients. Skin cancers were less common and gastrointestinal cancers more common as secondary malignancies in Japanese patients, suggesting ethnic differences.

Background and Methods: FLT3-internal tandem duplication (FLT3-ITD) is a type of mutation present in approximately 20-30% of patients with acute myeloid leukemia (AML) and is associated with poor prognosis. We performed a comprehensive genome profiling assay in patients with relapsed and refractory (R/R) AML, using the Foundation One Heme (F1H) panel, as a part of hematologic malignancies (HM)-SCREEN-Japan 01 (UMIN000035233), an actionable mutation profiling multicenter study. In this study, we analyzed the high frequency of FLT3 mutations in patients with R/R AML and found several patients who were positive for FLT3-N676K, a subclonal gene without concurrent ITD. Moreover, clonal evolution was observed in most patients who received kinase inhibitors, suggesting that mutations in signaling pathways downstream of FLT3 and activation of alternative pathways contribute to resistance mechanisms after FLT3 inhibitor treatment. Upon treatment failure during gilteritinib or quizartinib monotherapy, we can switch to another FLT3 inhibitor treatment in Japan. However, few reports have investigated clonal evolution after multiple FLT3 inhibitor treatment failure, and the mutational resistance profile remains unknown. Thus, we extended our investigation to examine clonal evolution during the progression of leukemia harboring FLT3-ITD and tyrosine kinase domain mutation (TKD) mutations. In this study, we performed serial comprehensive genome profiling analyses to evaluate time-dependent changes in genomic profiles of patients receiving the FLT3 inhibitors gilteritinib, and quizartinib in AML. Results: This study was initiated in January 2019, and 91 patients were recruited by March 2020. The median turnaround time between sending specimens and receiving results was 15 days (9 to 56 days). In this study, a higher incidence of FLT3 mutations was observed in patients with AML (28.6%, 26/91), and those with relapse/refractory (R/R) AML (64.8%, 59/91), FLT3-ITD (20.3%, 12/59), and FLT3-TKD (15.3%, 9/59), than previously reported in newly diagnosed patients. Particularly, FLT3 mutations were much more frequently observed in patients with R/R AML (35.6 %, 21/59), whereas those with newly diagnosed AML unfit for standard treatment (15.6 %, 5/32). Furthermore, FLT3-TKD mutations were found in 10 patients, who were potential candidates for treatment with FLT3 inhibitors, such as gilteritinib. The N676K mutation within the FLT3 tyrosine kinase domain 1, which is not detectable through conventional mutational analyses, was observed using a multiplex polymerase chain reaction in 19.2% (5 of 26) of patients who were FLT3mutation-positive, including those with subclonal mutations. Moreover, patients with RUNX1 mutation were present in this cohort, and this finding supports previous reports showing the association between the core binding factor protein complex and FLT3 N676K mutation in leukemia. Interestingly, FLT3-ITD mutations usually occur in the juxtamembrane domain, but we found three patients with other abnormalities, including ITDs in the tyrosine kinase domain, which are associated with poor prognosis. Meanwhile, during FLT3 inhibitor treatment, the resistant clonal expansion was observed due to activation of alternative pathways such as NRAS pathway or acquired FLT3 mutation. Not only activating these alternative pathways, but the cases in which TKD point mutation was added to FLT3-ITD, or new mutations were acquired without the additional mutation site among the cases showing FLT3 inhibitor resistance as the treatment progressed. Conclusions: We conclude that F1H mutational analyses for R/R AML harboring FLT3-ITD/TKD mutations may reveal novel therapeutic targets that are sensitive to FLT3 inhibitors. Moreover, improved biomarker analysis methods for detecting additional FLT3 alternations, like FLT3 N676K, could guide patient selection for the most suitable anti-FLT3 therapies. Furthermore, serial comprehensive genome profiling analysis at the time of AML progression, especially after tyrosine kinase inhibitor treatment, will provide valuable information for clinical decision-making. Table Disclosures Shibayama: Fujimoto: Honoraria; Pfizer: Honoraria; Bristol-Myers Squibb: Honoraria; Otsuka: Honoraria; Kyowa Kirin: Honoraria; Chugai: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Janssen: Honoraria, Research Funding; Novartis: Honoraria, Research Funding; Daiichi Sankyo: Honoraria; Nippon Shinyaku: Honoraria, Research Funding; Sumitomo Dainippon: Honoraria, Research Funding; Merck Sharp & Dohme: Research Funding; Takeda: Honoraria, Research Funding; Ono: Honoraria, Research Funding; Celgene: Membership on an entity's Board of Directors or advisory committees, Research Funding; Eisai: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Taiho: Research Funding; Shionogi: Research Funding; Teijin: Research Funding; Astellas: Research Funding; Sanofi: Honoraria; AstraZeneca: Honoraria, Membership on an entity's Board of Directors or advisory committees; AbbVie: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Mundi Pharma: Honoraria. Yamauchi:Otsuka: Research Funding; Ono Pharmaceutical: Honoraria; Chugai: Honoraria; Abbie: Research Funding; Solasia Pharma: Research Funding; Astellas: Research Funding; Daiichi Sankyo: Research Funding; Pfizer: Honoraria, Research Funding. Gotoh:Eisai: Honoraria; Alexion pharmaceuticals: Research Funding; Ono Pharmaceutical: Honoraria; Nippon Shinyaku: Honoraria; Takeda pharmaceutical: Honoraria; Taiho pharmaceutical: Honoraria; Chugai: Honoraria; Novartis: Research Funding. Yamamoto:Chugai: Consultancy, Honoraria, Research Funding; Eisai: Consultancy, Honoraria, Research Funding; Sanofi: Honoraria; Sumitomo Dainippon: Honoraria; Stemline Therapeutics: Consultancy; Otsuka: Consultancy, Honoraria, Research Funding; Pfizer: Honoraria; IQIVA/HUYA: Honoraria; HUYA: Consultancy; IQIVA/Incyte: Research Funding; Solasia Pharma: Research Funding; SymBio: Research Funding; Takeda: Consultancy, Honoraria, Research Funding; Yakult: Research Funding; Zenyaku: Research Funding; Astra-Zeneca: Consultancy, Research Funding; Bayer: Research Funding; Bristol-Myers Squibb: Honoraria; Aichi Cancer Center: Current Employment; Kyowa Kirin: Honoraria; Meiji Seika Pharma: Consultancy, Honoraria; Mochida: Honoraria; Gilead Sciences: Research Funding; Daiichi Sankyo: Consultancy; MSD: Consultancy, Honoraria, Research Funding; Mundipharma: Consultancy, Honoraria, Research Funding; Nippon Shinyaku: Honoraria, Research Funding; Novartis: Honoraria, Research Funding; Ono: Consultancy, Honoraria, Research Funding; Janssen: Honoraria; AbbVie: Consultancy, Honoraria, Research Funding; Celgene: Consultancy, Honoraria, Research Funding. Fujishima:Pfizer: Speakers Bureau. Takahashi:Novartis Pharma KK: Honoraria, Research Funding; Pfizer Japan Inc.: Honoraria, Research Funding; Bristol-Myers Squibb Company: Honoraria. Usuki:Apellis: Research Funding; Alexion: Research Funding, Speakers Bureau; Novartis: Research Funding, Speakers Bureau; Chugai: Research Funding. ONO:Astellas Pharma Inc.: Honoraria; TAIHO PHARMACEUTICAL CO., LTD.: Research Funding; Mundipharma K.K.: Honoraria; Otsuka Pharmaceutical Co., Ltd.: Honoraria; Novartis Pharma KK: Honoraria; Celgene: Honoraria, Research Funding; Bristol-Myers Squibb Company: Honoraria; Pfizer Japan Inc.: Honoraria; Chugai Pharmaceutical Co., Ltd.: Honoraria, Research Funding; ONO PHARMACEUTICAL CO., LTD.: Honoraria, Research Funding; Takeda Pharmaceutical Company Limited.: Honoraria; Kyowa Kirin Co., Ltd.: Honoraria, Research Funding; DAIICHI SANKYO COMPANY, LIMITED.: Honoraria; Janssen Pharmaceutical K.K: Honoraria; Eisai Co., Ltd.: Honoraria. Kuroda:Sysmex: Research Funding; Otsuka Pharmaceutical: Honoraria, Research Funding; Astellas Pharma: Honoraria, Research Funding; Takeda: Honoraria, Research Funding; Celgene: Consultancy, Honoraria, Research Funding; Abbvie: Consultancy, Honoraria; Ono Pharmaceutical: Honoraria, Research Funding; Nippon Shinyaku: Honoraria, Research Funding; Pfizer: Honoraria, Research Funding; Asahi Kasei: Research Funding; Shionogi: Research Funding; Dainippon Sumitomo Pharma: Honoraria, Research Funding; Daiichi Sankyo: Honoraria, Research Funding; Sanofi: Consultancy, Honoraria, Research Funding; Kyowa Kirin: Honoraria, Research Funding; Janssen Pharmaceutical K.K: Consultancy; Eisai: Honoraria, Research Funding; Fujimoto Pharmaceutical: Honoraria, Research Funding; Taiho Pharmaceutical: Research Funding; Bristol-MyersSquibb: Consultancy, Honoraria, Research Funding; Chugai Pharmaceutical: Honoraria, Research Funding; MSD: Research Funding. Izutsu:Incyte: Research Funding; Eisai: Research Funding; AstraZeneca: Research Funding; Abbvie pharmaceuticals: Research Funding; Chugai: Research Funding; Novartis: Research Funding; Celgene: Research Funding; Symbio: Research Funding; Solasia: Research Funding; Janssen: Research Funding; Yakult: Research Funding; HUYA Japan: Research Funding; Sanofi: Research Funding; Daiichi Sankyo: Research Funding; Bayer pharmaceuticals: Research Funding; Ono Pharmaceutical: Research Funding. Minami:Novartis Pharma KK: Honoraria; Pfizer Japan Inc.: Honoraria; Takeda: Honoraria; Bristol-Myers Squibb Company: Honoraria.

Vitamin B6 (VB6) deficiency contributes to oncogenesis and tumor progression in certain cancers, and is prevalent in cancer patients in general. VB6 is also an essential element of heme synthesis, and deficiency can lead to anemia. Primary myelofibrosis (PMF) and secondary myelofibrosis (sMF) are myeloproliferative neoplasms often presenting with anemia along with other cytopenias. We performed a prospective study to determine whether PMF and sMF patients suffer from VB6 deficiency, and whether VB6-deficient patients show improvement of anemias with VB6 supplementation. Twelve PMF patients and 11 sMF patients were analyzed. A total of 16 of 23 patients (69.6%) were found to have VB6 deficiency, but VB6 supplementation with pyridoxal phosphate hydrate did not elevate hemoglobin levels in deficient patients. None of the patients presented with vitamin B12, iron, or copper deficiencies. Four patients showed serum folate levels below the lower limit of normal and eight patients showed serum zinc levels below the lower limit of normal; however, these deficiencies were marginal and unlikely to contribute to anemia. Compared to VB6-sufficient patients, VB6-deficient patients showed significantly lower serum folate levels and higher serum copper levels. Studies elucidating the relationship of VB6 deficiency and etiology of PMF/sMF are warranted.

Accurate staging and evaluation of therapeutic effects are important in managing plasma-cell neoplasms. Diffusion-weighted imaging with body signal suppression magnetic resonance imaging (DWIBS-MRI) allows for acquisition of whole-body volumetric data without radiation exposure. This study aimed to investigate the usefulness of DWIBS-MRI in plasma-cell neoplasms. We retrospectively analyzed 29 and 8 Japanese patients with multiple myeloma and monoclonal gammopathy of undetermined significance, respectively, who underwent DWIBS-MRI. We conducted a histogram analysis of apparent diffusion coefficient values. The correlations between each histogram parameter and staging, cell maturation, prognosis, and treatment response were evaluated. We found that the apparent diffusion coefficient values in patients with monoclonal gammopathy of undetermined significance were lower than those in patients with multiple myeloma. Pretreatment apparent diffusion coefficient values of immature myeloma were lower than those of mature myeloma. Moreover, these values decreased in proportion to stage progression in Durie-Salmon classification system but showed no significant correlation with other staging systems or prognosis. Patients were stratified as responder, stable, and non-responder based on the International Myeloma Working Group criteria. The magnitude of changes in apparent diffusion coefficients differed significantly between responders and non-responders (0.154 ± 0.386 ×10–3 mm2/s vs. -0.307 ± 0.424 ×10–3 mm2/s, p = 0.003). Although its usefulness has yet to be established, DWIBS-MRI combined with apparent diffusion coefficient measurement allowed for excellent response evaluation in patients with multiple myeloma. Furthermore, apparent diffusion coefficient analysis using DWIBS-MRI may be useful in predicting cell maturation and total tumor volume.

Non-tuberculous mycobacterial (NTM) disease is a rare cause of neutropenic fever in patients with hematological malignancies. There are few studies on the optimal management for such patients with NTM. We report a case of myelodysplastic syndrome (MDS) treated by umbilical cord blood transplantation (CBT) after Mycobacterium kansasii (M. kansasii) pneumonia. A 38-year-old man diagnosed with MDS developed severe pneumonia during induction chemotherapy. Repeated sputum culture uncovered mycobacterium infection. Then, by the polymerase chain reaction of the bronchial lavage fluid, M. kansasii infection was proven. After 140 days of anti-NTM therapy, CBT was successfully carried out and the patient recovered without recurrence of NTM infection. This case provides valuable evidence that hematopoietic stem cell transplantation is feasible after a reliable diagnosis and continuous anti-NTM therapy.

Primary effusion lymphoma (PEL) is a large B-cell lymphoma that only proliferates proliferating effusion in the body cavity. It is associated with human herpesvirus 8 (HHV8).HHV8 negative effusion lymphoma, which is different from PEL in many ways, has also been reported and is referred to as HHV8-unrelated PEL-like lymphoma. This lymphoma is very rare and its clinical characteristics have not been fully clarified.A 79-year-old male developed HHV8-negative primary effusion lymphoma during treatment for myelodysplastic syndrome.Abdominal computed tomography revealed abdominal effusion, but did not show any evidence of a tumor mass or lymph node enlargement. A cytological analysis of his pleural effusion revealed atypical lymphoid cells that were negative for CD10, and positive for CD19 and CD20. Corticosteroids were administered to treat the abdominal effusion; however, the patient died of an exacerbation of lymphoma on the 20th day after the initiation of corticosteroid therapy. We herein report the case of an HIV seronegative elderly patient with HHV8-unrelated PEL-like lymphoma.

Human herpesvirus-6 (HHV-6) reactivation is an important complication in patients receiving umbilical cord blood transplantation (CBT). Chromosomally integrated human herpesvirus-6 (ciHHV-6) is a condition in which the complete HHV-6 genome is integrated into the host germline genome and is transmitted in a Mendelian manner. The influence of ciHHV-6 in recipients or donors in cases of CBT is unknown. We report the first case with ciHHV-6 that received CBT twice for acute lymphoblastic T-cell leukemia. HHV-6 DNA in peripheral blood leukocytes (PBLs) was examined over time through two CBTs. After the first CBT, the HHV-6 viral load was significantly reduced by conversion to PBLs derived from the first donor. During the second CBT, an increase in HHV-6 DNA in PBLs and plasma were observed. However, HHV-6 mRNA was not detected in either the sample before 2nd CBT or at the time of HHV-6 DNA elevation. It is considered that the HHV-6 DNA detected in PBLs and plasma samples might be the HHV-6 genome released due to tissue damage. This case suggests that physicians should be aware of HHV-6 DNA variability during allogeneic hematopoietic stem cell transplantation in ciHHV-6 patients.

Background Multiple myeloma (MM) is a type of hematological malignancy affecting the functions of plasma cells. The treatment of MM patients has changed dramatically with the use of new agents. However, unfortunately, it is still incurable. Therefore, a new approach for treating MM is still needed to improve patient outcomes. Methods Because the histone deacetylase (HDAC) and phosphoinositide 3-kinase (PI3K) pathway is a key signal in cancer cell biology, we investigated whether dual HDAC and PI3K inhibitors could suppress the myeloma cells. Results Gene expression of HDACs is high in myeloma cells. CUDC-907, a dual inhibitor of PI3K and HDAC, inhibits HDAC activity. Akt activity and expression of BCL-XL, MCL-1, and NF-κB p65 were reduced by CUDC-907 in a dose-dependent manner. The number of apoptotic and caspase 3/7-positive cells also increased in the myeloma cells. Combined treatment of myeloma cells with carfilzomib and CUDC-907 increased cytotoxicity compared to that observed with each drug alone. Conclusions Data from this study suggested that the administration of CUDC-907 might be a powerful strategy against myeloma cells, to enhance the cytotoxic effects of proteasome inhibitors.

The majority of patients with Philadelphia chromosome-negative myeloproliferative neoplasms (MPNs) harbor JAK2, CALR, or MPL mutations. We compared clinical manifestations of different subtypes of JAK2 and CALR mutations in Japanese patients with MPNs. Within our cohort, we diagnosed 166 patients as polycythemia vera (PV), 212 patients as essential thrombocythemia (ET), 23 patients as pre-primary myelofibrosis (PMF), 65 patients as overt PMF, and 27 patients as secondary myelofibrosis following the 2016 WHO criteria. Compared to patients with JAK2V617F-mutated PV, JAK2 exon 12-mutated PV patients were younger, showed lower white blood cell (WBC) counts, lower platelet counts, higher red blood cell counts, and higher frequency of thrombotic events. Compared to JAK2-mutated ET patients, CALR-mutated ET patients were younger, showed lower WBC counts, lower hemoglobin levels, higher platelet counts, and fewer thrombotic events. CALR type 1-like mutation was the dominant subtype in CALR-mutated overt PMF patients. Compared with JAK2V617F-mutated ET patients, JAK2V617F-mutated pre-PMF patients showed higher LDH levels, lower hemoglobin levels, higher JAK2V617F allele burden, and higher frequency of splenomegaly. In conclusion, Japanese patients with MPNs grouped by different mutation subtypes exhibit characteristics similar to those of their Western counterparts. In addition, ET and pre-PMF patients show different characteristics, even when restricted to JAK2V617F-mutated patients.

Chronic myeloid leukemia (CML) is a hematopoietic stem cell disorder characterized by the Philadelphia chromosome (Ph) which is associated with BCR-ABL fusion protein. ABL tyrosine kinase inhibitor...

Background: Recently, whole exome sequencing has been used for the next-generation sequencing of acute myeloid leukemia (AML), and certain gene mutations have been identified in patients with AML. The treatment strategies for leukemia have undergone drastic changes with the rapid development of new drugs. However, the proper use of newly developed agents poses a major challenge in AML treatment. Genome profiling analysis can be used to select the optimal treatment for patients with newly diagnosed AML. Methods and Results: Hematologic malignancies (HM)-SCREEN-Japan 01 is an actionable mutation profiling multicenter study of patients with newly diagnosed AML who cannot be treated with first standard treatment or patients who have relapsed/refractory AML (R/R-AML). The objective of this study was to evaluate the frequency and characteristics of cancer-related genomic alterations in patients with AML using a comprehensive genome profiling assay (FoundationOne®Heme (F1H)) and determine the quality of specimens used in gene analysis. Before participant recruitment, approval was obtained from the institutional review board at each participating institution. The trial was registered in the UMIN Clinical Trials Registry (UMIN000035233). This study was conducted at 17 participating institutions and had a sample size of 200. The eligibility criteria were as follows: 1) histological diagnosis of AML through bone marrow aspiration; 2) fulfillment of either of the following conditions: i) newly diagnosed AML unfit for standard treatment (ND-unfit AML) or ii) R/R-AML; 3) sufficient sample collection via bone marrow aspiration; 4) Age of participants 20 years or above during registration; 5) provision of written informed consent by participants. The primary outcome was the frequency of each genomic alteration, as determined using F1H, which is a comprehensive genome profiling test based on next-generation sequencing, in the AML specimens. The secondary outcome was the association between each genomic alteration and the clinicopathological characteristics, prognosis, and quality of specimens used in the genetic analysis. Serial genome profiling analyses were performed to evaluate the time-dependent changes in the genome profiles of patients administered FLT3 inhibitors, gilteritinib, and quizartinib for treating AML. One hundred and eighty-two patients were recruited, and the F1H report was successfully obtained for 177 patients (97.3%). The median age of the 66 patients with ND-unfit AML was 73 years (63-79 years), and that of the 105 patients with R/R-AML was 50 years (41-68 years). The median turnaround time was 13 days (minimum 8 days). Recurrent alterations were observed in FLT3 (28.7%), TP53 (21.6%), RUNX1 (20.5%), DNMT3A (18.7%), NPM1 (18.7%), ASXL1 (15.2%), TET2 (14.0%), KMT2A-rearrangement (13.5%), and NRAS (13.5%). IDH1 and/or IDH2 mutations were identified in specimens collected from 30 patients (17.5%). Compared with the prevalence in 2247 patients with AML in the US and Europe who underwent F1H analysis, the frequencies of mutations in FLT3 (28.7% vs. 20.5%) and TP53 (21.6% vs. 17.0%) were higher in this Japanese cohort. Mutations in IDH2, PTPN11, and SF3B1 were observed along with KMT2A rearrangement. Mutations in TP53 tended to be exclusive to the FLT3 mutation. In comparison between the ND-unfit AML and R/R-AML, mutations in TET2 and ASXL1 tended to be more frequnt in ND-unfit AML (17.9% vs. 7.0%, p=0.038, 18.9% vs. 8.5%, p=0.055, respectively). The median expression level of WT1 mRNA at the time of sample collection was 4,490 copies/μgRNA (n=158), and WT1 mutation was frequently found in the WT1-high expression group (13.9% vs. 3.8%, p=0.03), suggesting that the mutation of WT1 may cause overexpression of WT1 as an oncogene. Conclusions: In our evaluation of the suitability of F1H for HM-SCREEN-Japan 01, we successfully identified leukemia-associated genes that can be used as therapeutic targets in AML, which have rarely been identified thus far. Figure 1 Figure 1. Disclosures Yamauchi: Astellas: Research Funding; Abbie: Research Funding; Chugai: Honoraria; Pfizer: Honoraria, Research Funding; Ono Pharmaceutical: Honoraria; Otsuka: Research Funding; Daiichi Sankyo: Research Funding; Solasia Pharma: Research Funding. Shibayama: Celgene: Research Funding; Ono: Honoraria, Research Funding; Takeda: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Avvie: Honoraria, Research Funding; Eisai: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Novartis: Honoraria, Research Funding; Janssen: Honoraria, Research Funding; Chugai: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Essentia Pharma Japan: Research Funding; AstraZeneca: Honoraria, Membership on an entity's Board of Directors or advisory committees; Daiichi Sankyo: Honoraria; Fujimoto: Honoraria; Nippon Shinyaku: Honoraria; Sanofi: Honoraria; Bristol-Myers Squibb: Honoraria; Pfizer: Honoraria; Otsuka: Honoraria; Mundi Pharma: Honoraria. Kondo: Astellas Pharma Inc.: Consultancy, Honoraria; Otsuka Pharmaceutical: Honoraria, Research Funding; Novartis Pharma KK: Honoraria; Bristol-Myers Squibb: Honoraria; Sumitomo Dainippon Pharma: Honoraria; Sanwa Kagaku Kenkyusho: Consultancy. Yamamoto: Eisai: Honoraria, Research Funding; IQIVA/Incyte: Research Funding; IQIVA/HUYA: Honoraria; HUYA: Consultancy; Janssen: Honoraria; Kyowa Kirin: Honoraria; Meiji Seika Pharma: Consultancy, Honoraria, Research Funding; MSD: Honoraria; Mundipharma: Research Funding; Nippon Shinyaku: Honoraria, Research Funding; Novartis: Honoraria, Research Funding; Ono: Honoraria, Research Funding; Otsuka: Honoraria, Research Funding; Sanofi: Honoraria; Solasia Pharma: Research Funding; SymBio: Honoraria, Research Funding; Takeda: Honoraria, Research Funding; Yakult: Honoraria, Research Funding; Zenyaku: Honoraria, Research Funding; Micron: Honoraria; IQIVA/Genmab: Research Funding; ADC Therapeutics: Honoraria; Daiichi Sankyo: Honoraria; Chugai: Honoraria, Research Funding; Bristol-Myers Squibb/Celgene: Honoraria, Research Funding; AstraZeneca: Honoraria, Research Funding; AbbVie: Honoraria, Research Funding. Kuroda: Sanofi: Consultancy, Honoraria, Research Funding; Kyowa Kirin: Honoraria, Research Funding; Otsuka Pharmaceutical: Honoraria, Research Funding; Astellas Pharma: Honoraria, Research Funding; Takeda: Honoraria, Research Funding; Celgene: Consultancy, Honoraria, Research Funding; MSD: Research Funding; Abbvie: Consultancy, Honoraria; Ono Pharmaceutical: Honoraria, Research Funding; Eisai: Honoraria, Research Funding; Sysmex: Research Funding; Pfizer: Honoraria, Research Funding; Nippon Shinyaku: Honoraria, Research Funding; Shionogi: Research Funding; Asahi Kasei: Research Funding; Taiho Pharmaceutical: Research Funding; Fujimoto Pharmaceutical: Current Employment, Honoraria, Research Funding; Daiichi Sankyo: Honoraria, Research Funding; Dainippon Sumitomo Pharma: Honoraria, Research Funding; Chugai Pharmaceutical: Honoraria, Research Funding; Bristol-MyersSquibb: Consultancy, Honoraria, Research Funding; Janssen Pharmaceutical K.K: Consultancy. Usuki: Nippon Boehringer Ingelheim: Research Funding; Takeda: Research Funding, Speakers Bureau; Celgene: Research Funding, Speakers Bureau; Janssen: Research Funding; Ono: Research Funding, Speakers Bureau; Brisol-Myers Squibb: Research Funding, Speakers Bureau; Novartis: Research Funding, Speakers Bureau; Otsuka: Research Funding, Speakers Bureau; Sumitomo Dainippon: Research Funding; Daiichi Sankyo: Research Funding, Speakers Bureau; Symbio: Research Funding, Speakers Bureau; Gilead: Research Funding; Abbvie: Research Funding; Astellas: Research Funding, Speakers Bureau; Astellas-Amgen-Biopharma: Research Funding; Nippon shinyaku: Research Funding, Speakers Bureau; Kyowa Kirin: Research Funding, Speakers Bureau; Pfizer: Research Funding; Alexion: Speakers Bureau; Eisai: Speakers Bureau; MSD: Speakers Bureau; PharmaEssentia: Speakers Bureau; Yakult: Speakers Bureau; Mundipharma: Research Funding. Yoshimitsu: Sanofi: Honoraria; Takeda: Honoraria; Novartis: Honoraria. Ishitsuka: Eli Lilly: Research Funding; Mochida: Other: Personal fees, Research Funding; Eisai: Other: Personal fees, Research Funding; Sumitomo Dainippon Pharma: Other: Personal fees, Research Funding; Genzyme: Other: Personal fees; Astellas Pharma: Other: Personal fees, Research Funding; Pfizer: Other: Personal fees; Novartis: Other: Personal fees; Janssen Pharmaceuticals: Other: Personal fees; Taiho Pharmaceuticals: Other: Personal fees, Research Funding; Mundipharma: Other: Personal fees; Takeda: Other: Personal fees, Research Funding; BMS: Other; Chugai Pharmaceutical: Honoraria, Other: Personal fees, Research Funding; Celgene: Honoraria, Other: Personal fees; Ono Pharmaceutical: Other: Personal fees, Research Funding; Kyowa Kirin: Other: Personal fees, Research Funding; Daiichi Sankyo: Consultancy, Other: Personal fees; Shire: Other; Otsuka Pharmaceutical: Other: Personal fees; Teijin Pharma: Research Funding; MSD: Research Funding; Asahi kasei: Research Funding; Huya Japan: Other: Personal fees. Ono: DAIICHI SANKYO COMPANY, LIMITED.: Honoraria; Novartis Pharma KK: Honoraria; Bristol-Myers Squibb Company: Honoraria; Pfizer Japan Inc.: Honoraria; Otsuka Pharmaceutical Co., Ltd.: Honoraria; ONO PHARMACEUTICAL CO., LTD.: Honoraria, Research Funding; Takeda Pharmaceutical Company Limited.: Honoraria; Astellas Pharma Inc.: Honoraria; Eisai Co., Ltd.: Honoraria; Janssen Pharmaceutical K.K: Honoraria; Mundipharma K.K.: Honoraria; TAIHO PHARMACEUTICAL CO., LTD.: Research Funding; Kyowa Kirin Co., Ltd.: Honoraria, Research Funding; Chugai Pharmaceutical Co., Ltd.: Honoraria, Research Funding; Celgene: Honoraria, Research Funding; Merck Sharp & Dohme: Honoraria, Research Funding. Takahashi: Kyowahakko-Kirin: Research Funding; Ono: Research Funding; Asahikasei: Research Funding; Toyamakagaku: Research Funding; Eizai: Research Funding; Chugai: Research Funding; Otsuka Pharmaceutical: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Pfizer: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Novartis Pharmaceuticals: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau. Iyama: Otsuka: Honoraria, Research Funding; Novartis: Honoraria; Nippon Shinyaku: Honoraria; MSD: Research Funding; Otsuka Pharmaceuticals Factory: Honoraria; Otsuka Pharmaceuticals Factory: Honoraria; Daiichi Sankyo: Honoraria; CSL Behring: Honoraria; Astellas: Honoraria; Alexion Pharmaceuticals: Honoraria, Research Funding; Sanofi: Honoraria, Research Funding; SymBio Pharmaceuticals: Research Funding. Izutsu: Yakult: Research Funding; Takeda: Honoraria, Research Funding; Chugai: Honoraria, Research Funding; Daiichi Sankyo: Honoraria, Research Funding; Eisai: Honoraria, Research Funding; Fuji Film Toyama Chemical: Honoraria; Genmab: Honoraria, Research Funding; Huya Biosciences: Research Funding; Incyte: Research Funding; Janssen: Honoraria, Research Funding; Kyowa Kirin: Honoraria, Research Funding; MSD: Research Funding; Novartis: Honoraria, Research Funding; Ono Pharmaceutical: Honoraria, Research Funding; Pfizer: Research Funding; Solasia: Research Funding; Symbio: Honoraria; Celgene: Honoraria, Research Funding; Beigene: Research Funding; Bayer: Research Funding; AstraZeneca: Honoraria, Research Funding; Allergan Japan: Honoraria; AbbVie: Honoraria. Minami: Bristol-Myers Squibb Company: Honoraria; Novartis Pharma KK: Honoraria; Pfizer Japan Inc.: Honoraria; Takeda: Honoraria; Astellas: Honoraria; Ono: Research Funding; CMIC: Research Funding.

Background and Methods: NPM1 mutation and KMT2A(MLL)-rearrangement/amplification are present in approximately 27% and 8.5% patients with acute myeloid leukemia (AML), respectively (data from cBioPortal). Although they have different clinical features and prognostic impact, recent studies suggest that the MLL co-factor, menin, plays a key role in maintaining self-renewal of immature leukemic cells by upregulating transcription of HOXA and MEIS (Gundry et al.). However, the real-world epidemiology of these mutations and co-existing gene alterations have not been thoroughly investigated in Japan. We launched an actionable mutation profiling multicenter study entitled Hematologic Malignancies (HM)-SCREEN-Japan 01 (UMIN000035233). In this study, a comprehensive genomic assay was performed by Foundation One Heme (F1H) panel for patients with relapsed/refractory (R/R) AML as well as patients with newly-diagnosed (ND) AML who are ineligible for standard chemotherapy. Paraffin-embedded bone marrow samples were gathered from 17 Japanese faculties and the F1H reports were returned to the patients. Results: One-hundred-eighty-two patients were recruited in this study and the F1H report was successfully returned in 177 patients (97.3%). Median age of 68 patients with ND-AML was 73 [63-79] years and those of 109 patients with R/R-AML was 50 [40-68.5] years. Median turn-around time was 13 days (minimum 8 days).We found 32 patients (18.1%) with NPM1 mutation and 23 patients (13.0%) of KMT2A(MLL)-rearrangement/amplification out of the 177 patients. These two alterations were mutually exclusive in this study. The median age of patients with NPM1 mutation (NPM1 mt.) and KMT2A-rearrangement (KMT2A-r) were 56.5 [43.5-73.8] and 62 [45-71] years, respectively. Three quarters or more patients were R/R-AML in both groups. WT1 expression levels were much higher in patients with NPM1 mt. than the other group (6,000 [77-110,000] vs. 93 [34-5,800] copies/mcgRNA). The major amino acid alteration of NPM1 was a frameshift mutation at the 288 th histidine (W288fs*12). Patterns of KMT2A(MLL)-rearrangement included MLL fusion (e.g., MLL-MLLT3) and partial tandem duplication (PTD) in ten patients each. MLL amplification was observed in three patients. Frequently co-occurring mutations with NPM1 mt. included FLT3 (56.3%), DNMT3A (46.9%), TET2 (34.4%), WT1 (18.8%), IDH1 (18.8%), and IDH2 (15.6%). Those with KMT2A-r included FLT3 (39.1%), TP53 (26.1%), PTPN11 (21.7%), DNMT3A (17.4%), and IDH2 (17.4%). Mutations of RAS pathway-related genes (e.g., KRAS, NRAS, PTPN11, and NF1) were observed in five patients with NPM1 mt. (15.6%) and 11 patients (47.8%) with KMT2A-r. None of the six patients with TP53 mutation had NPM1 mutation. The prognostic impact of each genes is currently being analyzed. Conclusions: Approximately three in ten patients with AML had NPM1 mutation and/or KMT2A(MLL)-rearrangement/amplification. No single patient had both the alterations. FLT3 and DNA methylation-associated genes (e.g., DNMT3A and TET2) were frequently seen in patients with NPM1 mt. In contrast, TP53 and RAS pathway-related gene alterations (e.g., NRAS, KRAS, PTPT11 and NF1) were relatively dominant in patients with KMT2A-r. TP53 mutation seemed unlikely to occur along with NPM1 mutation. Figure 1 Figure 1. Disclosures Shibayama: Celgene: Research Funding; Ono: Honoraria, Research Funding; Takeda: Honoraria, Research Funding; Avvie: Honoraria, Research Funding; Eisai: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Novartis: Honoraria, Research Funding; Janssen: Honoraria, Research Funding; Chugai: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Essentia Pharma Japan: Research Funding; AstraZeneca: Honoraria, Membership on an entity's Board of Directors or advisory committees; Daiichi Sankyo: Honoraria; Fujimoto: Honoraria; Nippon Shinyaku: Honoraria; Sanofi: Honoraria; Bristol-Myers Squibb: Honoraria; Pfizer: Honoraria; Otsuka: Honoraria; Mundi Pharma: Honoraria. Yamauchi: Otsuka: Research Funding; Ono Pharmaceutical: Honoraria; Pfizer: Honoraria, Research Funding; Chugai: Honoraria; Abbie: Research Funding; Astellas: Research Funding; Daiichi Sankyo: Research Funding; Solasia Pharma: Research Funding. Kondo: Otsuka Pharmaceutical: Consultancy, Honoraria, Research Funding; Pfizer: Honoraria; Novartis Pharma KK: Honoraria; Bristol-Myers Squibb Company: Honoraria; Sumitomo Dainippon Pharma: Honoraria; Sanwa Kagaku Kenkyusho CO.,LTD: Consultancy; Astellas Pharma Inc.: Consultancy, Honoraria; Abbvie: Honoraria. Yamamoto: Bristol-Myers Squibb/Celgene: Honoraria, Research Funding; AstraZeneca: Honoraria, Research Funding; Chugai: Honoraria, Research Funding; Daiichi Sankyo: Honoraria; Eisai: Honoraria, Research Funding; IQIVA/Incyte: Research Funding; IQIVA/HUYA: Honoraria; HUYA: Consultancy; Janssen: Honoraria; Kyowa Kirin: Honoraria; Meiji Seika Pharma: Consultancy, Honoraria, Research Funding; MSD: Honoraria; Mundipharma: Research Funding; Nippon Shinyaku: Honoraria, Research Funding; Novartis: Honoraria, Research Funding; Ono: Honoraria, Research Funding; Otsuka: Honoraria, Research Funding; Sanofi: Honoraria; Solasia Pharma: Research Funding; SymBio: Honoraria, Research Funding; Takeda: Honoraria, Research Funding; Yakult: Honoraria, Research Funding; Zenyaku: Honoraria, Research Funding; Micron: Honoraria; IQIVA/Genmab: Research Funding; ADC Therapeutics: Honoraria; AbbVie: Honoraria, Research Funding. Kuroda: Fujimoto Pharmaceutical: Current Employment, Honoraria, Research Funding; Taiho Pharmaceutical: Research Funding; Asahi Kasei: Research Funding; Shionogi: Research Funding; Nippon Shinyaku: Honoraria, Research Funding; Pfizer: Honoraria, Research Funding; Sysmex: Research Funding; Eisai: Honoraria, Research Funding; Ono Pharmaceutical: Honoraria, Research Funding; Abbvie: Consultancy, Honoraria; MSD: Research Funding; Celgene: Consultancy, Honoraria, Research Funding; Takeda: Honoraria, Research Funding; Astellas Pharma: Honoraria, Research Funding; Otsuka Pharmaceutical: Honoraria, Research Funding; Kyowa Kirin: Honoraria, Research Funding; Sanofi: Consultancy, Honoraria, Research Funding; Daiichi Sankyo: Honoraria, Research Funding; Dainippon Sumitomo Pharma: Honoraria, Research Funding; Chugai Pharmaceutical: Honoraria, Research Funding; Bristol-MyersSquibb: Consultancy, Honoraria, Research Funding; Janssen Pharmaceutical K.K: Consultancy. Usuki: Astellas: Research Funding, Speakers Bureau; Abbvie: Research Funding; Gilead: Research Funding; Symbio: Research Funding, Speakers Bureau; Daiichi Sankyo: Research Funding, Speakers Bureau; Sumitomo Dainippon: Research Funding; Otsuka: Research Funding, Speakers Bureau; Novartis: Research Funding, Speakers Bureau; Brisol-Myers Squibb: Research Funding, Speakers Bureau; Ono: Research Funding, Speakers Bureau; Janssen: Research Funding; Celgene: Research Funding, Speakers Bureau; Takeda: Research Funding; Nippon Boehringer Ingelheim: Research Funding; Mundipharma: Research Funding; Astellas-Amgen-Biopharma: Research Funding; Nippon shinyaku: Research Funding, Speakers Bureau; Kyowa Kirin: Research Funding, Speakers Bureau; Pfizer: Research Funding; Alexion: Speakers Bureau; Eisai: Speakers Bureau; MSD: Speakers Bureau; PharmaEssentia: Speakers Bureau; Yakult: Speakers Bureau. Yoshimitsu: Novartis: Honoraria; Takeda: Honoraria; Sanofi: Honoraria. Ishitsuka: Kyowa Kirin: Other: Personal fees, Research Funding; Daiichi Sankyo: Consultancy, Other: Personal fees; Ono Pharmaceutical: Other: Personal fees, Research Funding; Celgene: Honoraria, Other: Personal fees; Chugai Pharmaceutical: Honoraria, Other: Personal fees, Research Funding; BMS: Other; Takeda: Other: Personal fees, Research Funding; Mundipharma: Other: Personal fees; Taiho Pharmaceuticals: Other: Personal fees, Research Funding; Janssen Pharmaceuticals: Other: Personal fees; Novartis: Other: Personal fees; Pfizer: Other: Personal fees; Astellas Pharma: Other: Personal fees, Research Funding; Genzyme: Other: Personal fees; Sumitomo Dainippon Pharma: Other: Personal fees, Research Funding; Eisai: Other: Personal fees, Research Funding; Mochida: Other: Personal fees, Research Funding; Shire: Other; Otsuka Pharmaceutical: Other: Personal fees; Teijin Pharma: Research Funding; MSD: Research Funding; Asahi kasei: Research Funding; Eli Lilly: Research Funding; Huya Japan: Other: Personal fees. Ono: DAIICHI SANKYO COMPANY, LIMITED.: Honoraria; Mundipharma K.K.: Honoraria; Celgene: Honoraria, Research Funding; Kyowa Kirin Co., Ltd.: Honoraria, Research Funding; Janssen Pharmaceutical K.K: Honoraria; Eisai Co., Ltd.: Honoraria; Astellas Pharma Inc.: Honoraria; Takeda Pharmaceutical Company Limited.: Honoraria; ONO PHARMACEUTICAL CO., LTD.: Honoraria, Research Funding; Otsuka Pharmaceutical Co., Ltd.: Honoraria; Pfizer Japan Inc.: Honoraria; Bristol-Myers Squibb Company: Honoraria; Novartis Pharma KK: Honoraria; Chugai Pharmaceutical Co., Ltd.: Honoraria, Research Funding; TAIHO PHARMACEUTICAL CO., LTD.: Research Funding; Merck Sharp & Dohme: Honoraria, Research Funding. Fujishima: Pfizer: Speakers Bureau. Takahashi: Toyamakagaku: Research Funding; Novartis Pharmaceuticals: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Pfizer: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Otsuka Pharmaceutical: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Chugai: Research Funding; Eizai: Research Funding; Asahikasei: Research Funding; Kyowahakko-Kirin: Research Funding; Ono: Research Funding. Iyama: Alexion Pharmaceuticals: Honoraria, Research Funding; Astellas: Honoraria; CSL Behring: Honoraria; Daiichi Sankyo: Honoraria; Otsuka Pharmaceuticals Factory: Honoraria; Otsuka Pharmaceuticals Factory: Honoraria; MSD: Research Funding; Nippon Shinyaku: Honoraria; Novartis: Honoraria; Otsuka: Honoraria, Research Funding; Sanofi: Honoraria, Research Funding; SymBio Pharmaceuticals: Research Funding. Izutsu: Symbio: Honoraria; Takeda: Honoraria, Research Funding; Solasia: Research Funding; Pfizer: Research Funding; Ono Pharmaceutical: Honoraria, Research Funding; Novartis: Honoraria, Research Funding; MSD: Research Funding; Kyowa Kirin: Honoraria, Research Funding; Janssen: Honoraria, Research Funding; Incyte: Research Funding; Huya Biosciences: Research Funding; Genmab: Honoraria, Research Funding; Fuji Film Toyama Chemical: Honoraria; Eisai: Honoraria, Research Funding; Daiichi Sankyo: Honoraria, Research Funding; Chugai: Honoraria, Research Funding; Celgene: Honoraria, Research Funding; Beigene: Research Funding; Bayer: Research Funding; AstraZeneca: Honoraria, Research Funding; Yakult: Research Funding; Allergan Japan: Honoraria; AbbVie: Honoraria. Minami: Bristol-Myers Squibb Company: Honoraria; Novartis Pharma KK: Honoraria; Pfizer Japan Inc.: Honoraria; Takeda: Honoraria; Astellas: Honoraria; Ono: Research Funding; CMIC: Research Funding.

Background and Methods: Acute myeloid leukemia (AML) bearing the RUNX1-RUNX1T1 fusion gene is known to be one of the core-binding factor AML (CBF-AML) which exerts relatively good prognosis. The RUNX1-RUNX1T1 fusion gene are present in approximately 3.5% of patients with AML (data from cBioPortal). However, the real-world epidemiology of this mutation and co-existing gene alterations have not been fully investigated in Japan. We launched an actionable mutation profiling multicenter study named Hematologic Malignancies (HM)-SCREEN-Japan 01 (UMIN000035233), in which a comprehensive genomic assay was performed by Foundation One Heme (F1H) panel for patients with relapsed/refractory (R/R) AML as well as patients with newly-diagnosed (ND) AML who were ineligible for standard chemotherapy. Paraffin-embedded bone marrow samples were gathered from 17 Japanese faculties and the F1H reports were returned to the patients. Results: We found 12 patients (6.8%) with the RUNX1-RUNX1T1 fusion gene out of 177 patients who joined this study and the F1H report was successfully retuned. Eight of these patients were enrolled as R/R AML and four were enrolled as ND AML who are ineligible for standard chemotherapy. Four (50%) of R/R patients were received allogeneic hematopoietic stem cell transplantation. Among the 12 patients with the RUNX1-RUNX1T1 fusion gene, eight (66.7%) had KIT mutation. The major amino acid alteration of KIT was D816V/Y and two patients had two different point-mutations of KIT (one with D816Y plus D816V and the other with D816V plus N822K). No particular mutations, other than KIT, were predominantly co-occurred with RUNX1-RUNX1T1 fusion gene. Especially in R/R patients, 75 % of them had the KIT mutation. Two R/R patients without the KITmutation had JAK2 V617F and FLT3 D835Y respectively. Conclusions: AML with RUNX1-RUNX1T1 fusion gene is currently not indicated for transplantation in the first remission. Previous studies have demonstrated that approximately 30% of patients with CBF-AML harbored the KIT mutations at diagnosis, which might be an indicator of poor prognosis. In our study, the KIT mutations were detected much more frequently than in previously studies of newly-diagnosed CBF-AML. This result may suggest that patients with the KIT mutations were concentrated because our study targeted AML patients who were R/R to prior therapy or ineligible for standard chemotherapy. In addition, no specific mutations highly related to the RUNX1-RUNX1T1 fusion gene were detected other than the KIT mutation, suggesting the KIT mutation might be a suitable molecular marker to predict poor prognosis in AML with the RUNX1-RUNX1T1 fusion gene. Our study revealed the importance of KIT mutations in patients with R/R AML with RUNX1-RUNX1T1 fusion gene, and that the KITmutations may be a promising therapeutic target for this population. Furthermore, it is interesting that driver mutations such as JAK2 and FLT3 mutation were detected in R/R patients without KIT mutation, although further investigation is needed. This suggests that comprehensive genomic assays are highly useful in establishing precision medicine, even in this type of AML, which is generally considered to have a good prognosis. Since most of R/R patients need allo-SCT, precision medicine targeting KIT may be considered for post-recurrence treatment in AML with RUNX1-RUNX1T1 fusion gene, such as bridge therapy to transplantation, in the future. Figure 1 Figure 1. Disclosures Shibayama: Janssen Pharmaceutical K.K.: Research Funding, Speakers Bureau; Nippon Shinyaku Co., Ltd.: Speakers Bureau; Fujimoto Pharmaceutical Corp.: Speakers Bureau; Daiichi Sankyo Co., Ltd.: Speakers Bureau; Chugai Pharmaceutical Co., Ltd.: Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; AstraZeneca K.K.: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; PharmaEssentia Japan KK: Research Funding; Eisai Co., Ltd.: Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Novartis Pharma K.K.: Research Funding, Speakers Bureau; Takeda Pharmaceutical Co., Ltd.: Research Funding, Speakers Bureau; AbbVie GK: Research Funding, Speakers Bureau; Celgene K.K.: Research Funding; Ono Pharmaceutical Co., Ltd.: Research Funding, Speakers Bureau; Sanofi K.K.: Speakers Bureau; Bristol-Myers Squibb K.K.: Speakers Bureau. Yamauchi: Daiichi Sankyo: Research Funding; Astellas: Research Funding; Abbie: Research Funding; Chugai: Honoraria; Pfizer: Honoraria, Research Funding; Ono Pharmaceutical: Honoraria; Otsuka: Research Funding; Solasia Pharma: Research Funding. Kondo: Astellas Pharma Inc.: Consultancy, Honoraria; Otsuka Pharmaceutical: Honoraria, Research Funding; Novartis Pharma KK: Honoraria; Bristol-Myers Squibb Company: Honoraria; Sumitomo Dainippon Pharma: Honoraria; Sanwa Kagaku Kenkyusho CO.,LTD: Consultancy. Yamamoto: IQIVA/Incyte: Research Funding; AstraZeneca: Honoraria, Research Funding; IQIVA/HUYA: Honoraria; HUYA: Consultancy; Janssen: Honoraria; Kyowa Kirin: Honoraria; Meiji Seika Pharma: Consultancy, Honoraria, Research Funding; MSD: Honoraria; Mundipharma: Research Funding; Nippon Shinyaku: Honoraria, Research Funding; Novartis: Honoraria, Research Funding; Ono: Honoraria, Research Funding; Otsuka: Honoraria, Research Funding; Sanofi: Honoraria; Solasia Pharma: Research Funding; SymBio: Honoraria, Research Funding; Takeda: Honoraria, Research Funding; Yakult: Honoraria, Research Funding; Zenyaku: Honoraria, Research Funding; Micron: Honoraria; IQIVA/Genmab: Research Funding; ADC Therapeutics: Honoraria; Eisai: Honoraria, Research Funding; Daiichi Sankyo: Honoraria; Chugai: Honoraria, Research Funding; Bristol-Myers Squibb/Celgene: Honoraria, Research Funding; AbbVie: Honoraria, Research Funding. Kuroda: Fujimoto Pharmaceutical: Current Employment, Honoraria, Research Funding; Taiho Pharmaceutical: Research Funding; Asahi Kasei: Research Funding; Shionogi: Research Funding; Nippon Shinyaku: Honoraria, Research Funding; Pfizer: Honoraria, Research Funding; Sysmex: Research Funding; Eisai: Honoraria, Research Funding; Ono Pharmaceutical: Honoraria, Research Funding; Abbvie: Consultancy, Honoraria; MSD: Research Funding; Celgene: Consultancy, Honoraria, Research Funding; Takeda: Honoraria, Research Funding; Astellas Pharma: Honoraria, Research Funding; Otsuka Pharmaceutical: Honoraria, Research Funding; Kyowa Kirin: Honoraria, Research Funding; Sanofi: Consultancy, Honoraria, Research Funding; Daiichi Sankyo: Honoraria, Research Funding; Dainippon Sumitomo Pharma: Honoraria, Research Funding; Chugai Pharmaceutical: Honoraria, Research Funding; Bristol-MyersSquibb: Consultancy, Honoraria, Research Funding; Janssen Pharmaceutical K.K: Consultancy. Usuki: Otsuka Pharmaceutical Co., Ltd.: Research Funding, Speakers Bureau; Novartis Pharma K.K.: Research Funding, Speakers Bureau; Ono Pharmaceutical Co., Ltd.: Research Funding, Speakers Bureau; Janssen Pharmaceutical K.K.: Research Funding; Celgene K.K.: Research Funding, Speakers Bureau; Takeda Pharmaceutical Co., Ltd.: Research Funding, Speakers Bureau; Nippon-Boehringer-Ingelheim Co., Ltd.: Research Funding; Mundipharma K.K.: Research Funding; Amgen-Astellas Biopharma K.K.: Research Funding; Nippon-Shinyaku Co., Ltd.: Research Funding, Speakers Bureau; Kyowa-Kirin Co., Ltd.: Research Funding, Speakers Bureau; Pfizer Japan Inc.: Research Funding, Speakers Bureau; Alexion Pharmaceuticals, Inc.: Research Funding, Speakers Bureau; Eisai Co., Ltd.: Speakers Bureau; MSD K.K.: Research Funding, Speakers Bureau; PharmaEssentia Japan KK: Research Funding, Speakers Bureau; Yakult Honsha Co., Ltd.: Research Funding, Speakers Bureau; Bristol-Myers-Squibb K.K.: Research Funding, Speakers Bureau; Sumitomo-Dainippon Pharma Co., Ltd.: Research Funding; Daiichi Sankyo Co., Ltd.: Research Funding, Speakers Bureau; SymBio Pharmaceuticals Ltd.: Research Funding, Speakers Bureau; Apellis Pharmaceuticals, Inc.: Research Funding; Gilead Sciences, Inc.: Research Funding; AbbVie GK: Research Funding, Speakers Bureau; Astellas Pharma Inc.: Research Funding, Speakers Bureau; Incyte Biosciences Japan G.K.: Research Funding; Chugai Pharmaceutical Co., Ltd.: Research Funding, Speakers Bureau; Sanofi K.K.: Speakers Bureau; Amgen K.K.: Research Funding. Yoshimitsu: Sanofi: Honoraria; Takeda: Honoraria; Novartis: Honoraria. Ishitsuka: BMS: Other; Takeda: Other: Personal fees, Research Funding; Mundipharma: Other: Personal fees; Taiho Pharmaceuticals: Other: Personal fees, Research Funding; Janssen Pharmaceuticals: Other: Personal fees; Novartis: Other: Personal fees; Pfizer: Other: Personal fees; Astellas Pharma: Other: Personal fees, Research Funding; Genzyme: Other: Personal fees; Sumitomo Dainippon Pharma: Other: Personal fees, Research Funding; Eisai: Other: Personal fees, Research Funding; Chugai Pharmaceutical: Honoraria, Other: Personal fees, Research Funding; Celgene: Honoraria, Other: Personal fees; Ono Pharmaceutical: Other: Personal fees, Research Funding; Kyowa Kirin: Other: Personal fees, Research Funding; Daiichi Sankyo: Consultancy, Other: Personal fees; MSD: Research Funding; Teijin Pharma: Research Funding; Otsuka Pharmaceutical: Other: Personal fees; Shire: Other; Mochida: Other: Personal fees, Research Funding; Asahi kasei: Research Funding; Eli Lilly: Research Funding; Huya Japan: Other: Personal fees. Ono: Novartis Pharma KK: Honoraria; Merck Sharp & Dohme: Honoraria, Research Funding; Bristol-Myers Squibb Company: Honoraria; Pfizer Japan Inc.: Honoraria; Otsuka Pharmaceutical Co., Ltd.: Honoraria; ONO PHARMACEUTICAL CO., LTD.: Honoraria, Research Funding; Takeda Pharmaceutical Company Limited.: Honoraria; Astellas Pharma Inc.: Honoraria; Eisai Co., Ltd.: Honoraria; Janssen Pharmaceutical K.K: Honoraria; DAIICHI SANKYO COMPANY, LIMITED.: Honoraria; Mundipharma K.K.: Honoraria; TAIHO PHARMACEUTICAL CO., LTD.: Research Funding; Chugai Pharmaceutical Co., Ltd.: Honoraria, Research Funding; Kyowa Kirin Co., Ltd.: Honoraria, Research Funding; Celgene: Honoraria, Research Funding. Takahashi: Kyowahakko-Kirin: Research Funding; Ono: Research Funding; Asahikasei: Research Funding; Toyamakagaku: Research Funding; Eizai: Research Funding; Chugai: Research Funding; Otsuka Pharmaceutical: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Pfizer: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Novartis Pharmaceuticals: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau. Iyama: Novartis: Honoraria; Nippon Shinyaku: Honoraria; MSD: Research Funding; Otsuka Pharmaceuticals Factory: Honoraria; Otsuka Pharmaceuticals Factory: Honoraria; Daiichi Sankyo: Honoraria; CSL Behring: Honoraria; Astellas: Honoraria; Alexion Pharmaceuticals: Honoraria, Research Funding; Otsuka: Honoraria, Research Funding; Sanofi: Honoraria, Research Funding; SymBio Pharmaceuticals: Research Funding. Izutsu: Celgene: Honoraria, Research Funding; Daiichi Sankyo: Honoraria, Research Funding; Eisai: Honoraria, Research Funding; HUYA Bioscience International: Research Funding; Kyowa Kirin: Honoraria, Research Funding; Takeda Pharmaceutical: Honoraria, Research Funding; Yakult: Research Funding; AbbVie: Honoraria, Research Funding; AstraZeneca: Honoraria, Research Funding; Bayer: Research Funding; Beigene: Research Funding; Chugai: Honoraria, Research Funding; Genmab: Honoraria, Research Funding; Incyte: Research Funding; Janssen: Honoraria, Research Funding; MSD: Research Funding; Novartis: Honoraria, Research Funding; Ono: Honoraria, Research Funding; Pfizer: Research Funding; Symbio: Honoraria, Research Funding; Allergan Japan: Honoraria; FUJI FILM Toyama Chemical: Honoraria. Minami: Bristol-Myers Squibb Company: Honoraria; Pfizer Japan Inc.: Honoraria; Novartis Pharma KK: Honoraria; Takeda: Honoraria; Astellas: Honoraria; Ono: Research Funding; CMIC: Research Funding.

Background and Methods: FMS-like tyrosine kinase 3 (FLT3) internal tandem duplication (FLT3-ITD) and tyrosine kinase domain mutation (FLT3-TKD) are types of mutations present in approximately 30% of patients with acute myeloid leukemia (AML). Currently, FLT3 inhibitors (FLT3i) are available in clinical practice, and the second-generation FLT3i, gilteritinib and quizartinib, are being used in Japan. However, the actual epidemiology of FLT3 mutations and co-existing gene alterations, particularly resistance mechanisms after FLT3i treatment, have not been thoroughly investigated in a Japanese population. Therefore, we conducted an actionable mutation profiling multicenter study, Hematologic Malignancies (HM)-SCREEN-Japan 01 (UMIN000035233), in which a comprehensive genomic assay was performed using the FoundationOne Heme (F1H) panel for patients with relapsed/refractory (R/R) AML and patients with newly diagnosed AML who were ineligible for standard chemotherapy (ND unfit). Paraffin-embedded bone marrow samples were used for next-generation sequencing (NGS) examination using the F1H panel. We analyzed the relationships between FLT3 gene mutations and other mutations and then chronologically evaluated the variant allele frequency (VAF) of gene mutations in the genomic profiles of patients with AML receiving FLT3i. Results: Of the 171 patients who participated in this study, 49 (28.7%) had FLT3 mutations. FLT3-ITD and FLT3-TKD accounted for 59% and 43% of all cases of FLT3 mutations, respectively. Two patients (4%) were found to have dual mutations: one with FLT3-ITD plus FLT3-TKD and another with FLT3-ITD plus FLT3-F691L. Eight patients (4.5%) were found to have the FLT3-N676K mutation, which is sensitive to gilteritinib but undetectable by currently available PCR-based companion diagnostic tools in Japan. Frequently co-occurring mutations included those of NPM1 (37%), DNMT3A (33%), IDH1/IDH2 (27%), WT1 (24%), and RUNX1 (22%). Mutations in RAS pathway-related genes (e.g., KRAS, NRAS, and PTPN11) were observed in 15 patients (31%). No gene alteration showed statistically significant co-occurrence with the FLT3mutation. However, the median number of mutations that co-exist with FLT3-TKD was slightly higher than that of FLT3-ITD (four genes [3-5] vs. three genes [2-5]). Sequential changes in the VAF of each gene alteration were investigated in nine patients with FLT3 mutations who eventually gained resistance to FLT3i. It was suggested that there were various patterns in clone evolution. Some showed the acquisition of not only CBL or NRAS as RAS pathways, but also other driver mutations: one showed a persistent FLT3mutation, one showed FLT3-ITD plus FLT3-TKD, and one showed a newly acquired FLT3 mutation substituting an existing FLT3 mutation. We also found that founder mutations, such as the DNMT3Amutation, remain even after eradication of FLT3 mutation during treatment with FLT3i, which could be the cause of the outcome of complete remission with incomplete hematologic recovery. Conclusions: This is the first report to analyze R/R and ND unfit AML cases in a Japanese cohort using F1H NGS, revealing a higher incidence of FLT3-ITD/TKD mutations than previously reported. Therefore, F1H mutational analyses for R/R and ND unfit AML patients harboring FLT3-ITD/TKD mutations may reveal novel therapeutic targets that are sensitive to FLT3i. Samples from these patients showed non-canonical gain-of-function mutations, such as N676K, S451F, V592D, and F691L, which could guide the selection of optimal anti-FLT3 therapies. In addition, longitudinal NGS analysis revealed clonal evolution in cases in which resistance to the FLT3i, gilteritinib and quizartinib were observed. Time-dependent analysis of allele frequencies can help evaluate the details of leukemia clonal evolution and provide optimal treatment options. Figure Legends Fig.1 Overview of gene mutations using F1H NGS analyses. The color of each column indicates the type of genetic mutation. Blue column; point mutation/insertion/deletion, green column; fusion gene, purple column; dual mutations. Fig.2 The chronological changes of leukemic cells fractions bearing each gene mutations during treatment with FLT3 inhibitors, gilteritinib and quizartinib. Figure 1 Figure 1. Disclosures Shibayama: Otsuka: Honoraria; Pfizer: Honoraria; Bristol-Myers Squibb: Honoraria; Sanofi: Honoraria; Nippon Shinyaku: Honoraria; Fujimoto: Honoraria; Daiichi Sankyo: Speakers Bureau; AstraZeneca: Honoraria, Membership on an entity's Board of Directors or advisory committees; Chugai: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Janssen: Honoraria, Research Funding; Novartis: Research Funding, Speakers Bureau; Eisai: Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; AbbVie: Research Funding, Speakers Bureau; Takeda: Research Funding, Speakers Bureau; Ono: Research Funding, Speakers Bureau; Celgene: Research Funding; Mundi Pharma: Honoraria; Essentia Pharma Japan: Research Funding. Yamauchi: Otsuka: Research Funding; Ono Pharmaceutical: Honoraria; Pfizer: Honoraria, Research Funding; Chugai: Honoraria; Abbie: Research Funding; Astellas: Research Funding; Daiichi Sankyo: Research Funding; Solasia Pharma: Research Funding. Kondo: Sumitomo Dainippon Pharma Co., Ltd.: Honoraria; Bristol-Myers Squibb Company: Honoraria; Novartis Pharma KK: Honoraria; Otsuka Pharmaceutical Co., Ltd.: Honoraria, Research Funding; Astellas Pharma Inc.: Consultancy, Honoraria; SANWA KAGAKU KENKYUSHO CO.,LTD.: Consultancy. Yamamoto: IQIVA/Genmab: Research Funding; Micron: Honoraria; Zenyaku: Honoraria, Research Funding; Yakult: Honoraria, Research Funding; Takeda: Honoraria, Research Funding; SymBio: Honoraria, Research Funding; Solasia Pharma: Research Funding; Sanofi: Honoraria; Otsuka: Honoraria, Research Funding; Ono: Honoraria, Research Funding; Novartis: Honoraria, Research Funding; Nippon Shinyaku: Honoraria, Research Funding; Mundipharma: Research Funding; MSD: Honoraria; Meiji Seika Pharma: Consultancy, Honoraria, Research Funding; Kyowa Kirin: Honoraria; Janssen: Honoraria; HUYA: Consultancy; IQIVA/HUYA: Honoraria; IQIVA/Incyte: Research Funding; Eisai: Honoraria, Research Funding; Daiichi Sankyo: Honoraria; Chugai: Honoraria, Research Funding; Bristol-Myers Squibb/Celgene: Honoraria, Research Funding; AstraZeneca: Honoraria, Research Funding; AbbVie: Honoraria, Research Funding; ADC Therapeutics: Honoraria. Kuroda: Kyowa Kirin: Honoraria, Research Funding; Otsuka Pharmaceutical: Honoraria, Research Funding; Astellas Pharma: Honoraria, Research Funding; Takeda: Honoraria, Research Funding; Celgene: Consultancy, Honoraria, Research Funding; MSD: Research Funding; Abbvie: Consultancy, Honoraria; Ono Pharmaceutical: Honoraria, Research Funding; Eisai: Honoraria, Research Funding; Sysmex: Research Funding; Pfizer: Honoraria, Research Funding; Nippon Shinyaku: Honoraria, Research Funding; Shionogi: Research Funding; Asahi Kasei: Research Funding; Taiho Pharmaceutical: Research Funding; Fujimoto Pharmaceutical: Current Employment, Honoraria, Research Funding; Dainippon Sumitomo Pharma: Honoraria, Research Funding; Daiichi Sankyo: Honoraria, Research Funding; Sanofi: Consultancy, Honoraria, Research Funding; Chugai Pharmaceutical: Honoraria, Research Funding; Bristol-MyersSquibb: Consultancy, Honoraria, Research Funding; Janssen Pharmaceutical K.K: Consultancy. Usuki: Otsuka Pharmaceutical Co., Ltd.: Research Funding, Speakers Bureau; Novartis Pharma K.K.: Research Funding, Speakers Bureau; Ono Pharmaceutical Co., Ltd.: Research Funding, Speakers Bureau; Janssen Pharmaceutical K.K.: Research Funding; Celgene K.K.: Research Funding, Speakers Bureau; Takeda Pharmaceutical Co., Ltd.: Research Funding, Speakers Bureau; Nippon-Boehringer-Ingelheim Co., Ltd.: Research Funding; Mundipharma K.K.: Research Funding; Amgen-Astellas Biopharma K.K.: Research Funding; Nippon-Shinyaku Co., Ltd.: Research Funding, Speakers Bureau; Kyowa-Kirin Co., Ltd.: Research Funding, Speakers Bureau; Pfizer Japan Inc.: Research Funding, Speakers Bureau; Alexion Pharmaceuticals, Inc.: Research Funding, Speakers Bureau; Eisai Co., Ltd.: Speakers Bureau; MSD K.K.: Research Funding, Speakers Bureau; PharmaEssentia Japan KK: Research Funding, Speakers Bureau; Yakult Honsha Co., Ltd.: Research Funding, Speakers Bureau; Daiichi Sankyo Co., Ltd.: Research Funding, Speakers Bureau; Sumitomo-Dainippon Pharma Co., Ltd.: Research Funding; SymBio Pharmaceuticals Ltd.: Research Funding, Speakers Bureau; Gilead Sciences, Inc.: Research Funding; Bristol-Myers-Squibb K.K.: Research Funding, Speakers Bureau; Apellis Pharmaceuticals, Inc.: Research Funding; AbbVie GK: Research Funding, Speakers Bureau; Astellas Pharma Inc.: Research Funding, Speakers Bureau; Incyte Biosciences Japan G.K.: Research Funding; Chugai Pharmaceutical Co., Ltd.: Research Funding, Speakers Bureau; Sanofi K.K.: Speakers Bureau; Amgen K.K.: Research Funding. Yoshimitsu: Novartis: Honoraria; Takeda: Honoraria; Sanofi: Honoraria. Ishitsuka: Eisai: Other: Personal fees, Research Funding; Sumitomo Dainippon Pharma: Other: Personal fees, Research Funding; Genzyme: Other: Personal fees; Astellas Pharma: Other: Personal fees, Research Funding; Pfizer: Other: Personal fees; Novartis: Other: Personal fees; Janssen Pharmaceuticals: Other: Personal fees; Taiho Pharmaceuticals: Other: Personal fees, Research Funding; Mundipharma: Other: Personal fees; Takeda: Other: Personal fees, Research Funding; BMS: Other; Chugai Pharmaceutical: Honoraria, Other: Personal fees, Research Funding; Celgene: Honoraria, Other: Personal fees; Ono Pharmaceutical: Other: Personal fees, Research Funding; Kyowa Kirin: Other: Personal fees, Research Funding; Daiichi Sankyo: Consultancy, Other: Personal fees; MSD: Research Funding; Teijin Pharma: Research Funding; Otsuka Pharmaceutical: Other: Personal fees; Shire: Other; Mochida: Other: Personal fees, Research Funding; Asahi kasei: Research Funding; Eli Lilly: Research Funding; Huya Japan: Other: Personal fees. Ono: Kyowa Kirin Co., Ltd.: Honoraria, Research Funding; Celgene: Honoraria, Research Funding; Janssen Pharmaceutical K.K: Honoraria; Eisai Co., Ltd.: Honoraria; Astellas Pharma Inc.: Honoraria; Takeda Pharmaceutical Company Limited.: Honoraria; ONO PHARMACEUTICAL CO., LTD.: Honoraria, Research Funding; Otsuka Pharmaceutical Co., Ltd.: Honoraria; Pfizer Japan Inc.: Honoraria; Bristol-Myers Squibb Company: Honoraria; Novartis Pharma KK: Honoraria; Chugai Pharmaceutical Co., Ltd.: Honoraria, Research Funding; DAIICHI SANKYO COMPANY, LIMITED.: Honoraria; Mundipharma K.K.: Honoraria; TAIHO PHARMACEUTICAL CO., LTD.: Research Funding; Merck Sharp & Dohme: Honoraria, Research Funding. Takahashi: Kyowahakko-Kirin: Research Funding; Toyamakagaku: Research Funding; Otsuka Pharmaceutical: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Pfizer: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Novartis Pharmaceuticals: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Chugai: Research Funding; Eizai: Research Funding; Asahikasei: Research Funding; Ono: Research Funding. Iyama: SymBio Pharmaceuticals: Research Funding; Astellas: Honoraria; CSL Behring: Honoraria; Daiichi Sankyo: Honoraria; Otsuka Pharmaceuticals Factory: Honoraria; Otsuka Pharmaceuticals Factory: Honoraria; MSD: Research Funding; Nippon Shinyaku: Honoraria; Novartis: Honoraria; Otsuka: Honoraria, Research Funding; Sanofi: Honoraria, Research Funding; Alexion Pharmaceuticals: Honoraria, Research Funding. Izutsu: Allergan Japan: Honoraria; Symbio: Honoraria, Research Funding; Pfizer: Research Funding; Ono: Honoraria, Research Funding; Novartis: Honoraria, Research Funding; MSD: Research Funding; Janssen: Honoraria, Research Funding; Incyte: Research Funding; Genmab: Honoraria, Research Funding; Chugai: Honoraria, Research Funding; Beigene: Research Funding; Bayer: Research Funding; AstraZeneca: Honoraria, Research Funding; AbbVie: Honoraria, Research Funding; Yakult: Research Funding; Takeda Pharmaceutical: Honoraria, Research Funding; Kyowa Kirin: Honoraria, Research Funding; HUYA Bioscience International: Research Funding; Eisai: Honoraria, Research Funding; Daiichi Sankyo: Honoraria, Research Funding; Celgene: Honoraria, Research Funding; FUJI FILM Toyama Chemical: Honoraria. Minami: Bristol-Myers Squibb Company: Honoraria; Pfizer Japan Inc.: Honoraria; Takeda: Honoraria; Novartis Pharma KK: Honoraria; Astellas: Honoraria; Ono: Research Funding; CMIC: Research Funding.

Introduction: Multiple myeloma (MM) is a uniformly fatal disorder of B cells characterized by the clonal expansion of plasma cells in the bone marrow. The treatment of MM patients has been dramatically changed by new agents such as proteasome inhibitors and immunomodulatory drugs, however, many patients will relapse even if new agents provide therapeutic advantages. Therefore, a new strategy is still needed to increase MM patient survival. Metabolic reprogramming is recognized as one of the hallmarks of cancer cells. Glutamine is the most abundant circulating amino acid in blood, glutamine metabolism through glutaminolysis may be associated with myeloma cell maintenance and survival. Materials and Methods: In this study, we investigated whether glutaminolysis was involved the proliferation in myeloma cells. We also investigated whether glutaminase (GLS) inhibitor, CB-839 could suppress myeloma cells and enhance the sensitivity of myeloma cells to histone deacetylase (HDAC) inhibition. Results: We first investigated the relationship between glutamine transporter or GLS gene expression and MM patients by microarray gene expression data from the online Gene Expression Omnibus (GEO). Glutamine transporter genes such as SLC38A1 and SLC1A5 were increased in myeloma and plasma cell leukemia cells (GSE13591). In contrast, GLS1 expression was not changed. We next investigated the glutaminolysis in myeloma cells. Deprivation of glutamine in culture medium revealed that cellular growth inhibition and cell cycle arrest at G0/G1 phase. Gene expression of AURKA (aurora kinase A), AURKB (aurora kinase B), HSP90AA1 (Heat Shock Protein 90 Alpha Family Class A Member 1) and CCNB1 (cyclin B1) were reduced from the public microarray datasets (GSE59931) and protein expressions were also reduced by immunoblot analysis. We next evaluated the effect of GLS inhibitor, CB-839. 72 h treatment of MM cells were inhibited by CB-839 in a dose dependent manner. Cellular cytotoxicity was also increased. Glutamine is converted by GLS into glutamate and alpha-ketoglutarate (α-KG), and related nicotinamide adenine dinucleotide phosphate (NADP) production. Intracellular α-KG and NADPH were reduced by CB-839. As metabolites are the substrates used to generate chromatin modification including acetylation of histone, we investigated HDAC inhibitor, panobinostat in myeloma cells. 72 h treatment of MM cells were inhibited by panobinostat and histone acetylation was increased. Combined treatment with panobinostat and CB-839 caused more cytotoxicity than each drug alone. Panobinostat and CB-839 also inhibited bortezomib resistant cells. Caspase 3/7 activity and cellular cytotoxicity were also increased. Proteasomal activity was reduced. Adenosine triphosphate (ATP) is the most important source of energy for intracellular reactions. Intracellular ATP levels drastically decreased. Because mitochondria generate ATP and participate in signal transduction and cellular pathology and cell death. The quantitative analysis of JC-1 stained cells changed mitochondrial membrane potential in cell death, which were induced by panobinostat and CB-839 on myeloma cells. Immunoblot analysis revealed that protein expression of aurora kinase A, aurora kinase B, HSP90 and cyclin B1 were reduced, and cleaved caspase 3 and γ- H2AX were increased by panobinostat and CB-839 treatment. GLS shRNA transfectant cells were inhibited cellular proliferation and sub-G1 phase was increased by cell cycle analysis. GLS shRNA transfectant cells were increased the sensitivity of panobinostat compared to control cells. Conclusion: The glutaminolysis is involved myeloma cell proliferation and GLS inhibitor is effective to myeloma cells and enhance cytotoxic effects of HDAC inhibitors. We also provide the promising clinical relevance as a candidate drug for treatment of myeloma patients. Disclosures No relevant conflicts of interest to declare.

Background Controlling serum cholesterol is critical to prevent cardiovascular disease in patients with dyslipidaemia. Guidelines emphasise the need to select treatment for dyslipidaemia based on specific patient profiles; however, there is little information about the serum cholesterol levels of patients in each profile in Japan. Therefore, we aimed to describe the serum cholesterol levels and prevalence of uncontrolled cases in Japanese patients with dyslipidaemia. Methods We included data for patients with dyslipidaemia between 2003 and 2007 from the BioBank Japan Project (66 hospitals). Then, we reported their serum cholesterol levels by age, body mass index, glycaemic control (glycated haemoglobin A1c), blood pressure, smoking, drinking, comorbidity and medication profiles. Results We included 22,189 male and 21,545 female patients. The mean serum low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), triglyceride (TG) and non-HDL-C levels in males were 117.4 mg/dL, 51.0 mg/dL, 187.6 mg/dL and 153.6 mg/dL, respectively; the corresponding levels in females were 129.5 mg/dL, 60.5 mg/dL, 144.9 mg/dL and 157.9 mg/dL, respectively. In both males and females, the LDL-C levels were the highest in the following profiles: age 19–44 years, body mass index 18.5–22 kg/m2, glycated haemoglobin A1c, Highlights • Evidence of serum cholesterol control in Japanese dyslipidaemic patients is scarce. • We analysed data for a large-scale population in hospital settings. • Our findings provide serum cholesterol levels by different risk profiles. • Serum lipid levels were the lowest in the youngest patients. • Data should be carefully applied to patients with mild hyperlipidaemia.

Background:Recently, whole exome sequencing has been performed for acute myeloid leukemia (AML) by next generation sequencing. The results revealed that certain gene mutations are identified in patients with AML. Among them,FLT3(28%),NPM1(27%),DNMT3A(26%), andIDH1/2(20%) mutations are observed in 20 to 30% of cases, while the frequencies of more than 10 other types of mutations are less than 10%. Some of these low frequency mutations are actionable mutations, which are defined as genetic DNA aberrations that are expected to elicit a response to an approved targeted therapy that is available for off-label treatment or available in clinical trials. Thus, the treatment strategies for leukemia are drastically changing with the rapid development of new drugs. Moving forward, the proper use of new agents is one of the major AML treatment issues. Especially, genome profiling analysis for newly diagnosed patients will be needed to select an optimal first line treatment. The HM-SCREEN-Japan 01 is an actionable mutation profiling multicenter study of patients with newly diagnosed AML who are unsuitable for the first standard treatment or have relapsed/refractory AML. The objective of this study is to evaluate the frequency and characteristics of cancer-related genome alterations in AML using a comprehensive genome profiling assay (FoundationOne®Heme) and determine the quality of specimens that contribute to the gene analysis. Approval was obtained from the Institutional Review Board prior to starting patient accrual at each institution. This trial has been registered at the UMIN Clinical Trials Registry as UMIN000035233. Methods:This study was conducted by 17 participating institutions, with a sample size of 200. The eligibility criteria were as follows: 1) histological diagnosis of AML through bone marrow aspiration; 2) either of the following conditions fulfilled, i) patients with newly diagnosed AML unfit for standard treatment or ii) patients with relapsed/refractory AML; 3) sufficient sample is collected by bone marrow aspiration; 4) age at registration is 20 years or older; 5) written informed consent is taken. The primary outcome was the frequency of each genomic alteration in leukemia using FoundationOne®Heme (F1H), which is a comprehensive genomic profile that applies next-generation sequencing. The secondary outcomes evaluated the association between each cancer genome alteration and clinicopathological characteristics, prognosis, and quality of the specimens that contributed to the genetic analysis. In this study, we also performed serial genome profiling analyses to evaluate the time-dependent changes in genomic profiles in patients administered FLT3 inhibitors, gilteritinib, and quizartinib for AML. Results:This study commenced in January 2019, and 91 patients were recruited by March 2020. The median turnaround time between sending specimens and receiving results was 15 days (9 to 56 days). Of the 91 patients, 35.2% (32/91) were newly diagnosed with AML and unfit for standard treatment and 64.8% (59/91) had relapsed/refractory AML. Mutations were observed in the following genes in all 91 patients:FLT3(28.6%),RUNX1(25.0%),TP53(20.1%),DNMT3A(19.8%),NPM1(18.7%),IDH1/2(17.6%),CEBPA(16.5%),KMT2A(14.3%),NRAS(13.2%),TET2(12.1%),ASXL1(12.1%), and EZH2(2.2%). In 32 patients with newly diagnosed AML, mutations were observed in the following genes:FLT3(28.6%),RUNX1(20.3%),TP53(18.8%),DNMT3A(15.6%),NPM1(12.5%),IDH1/2(15.6%),CEBPA(15.6%),KMT2A(6.0%),NRAS(12.5%),TET2(9.0%),ASXL1(21.9%), and EZH2(6.3%). In 59 patients with relapsed/refractory AML, mutations were observed in the following genes:FLT3(28.6%),RUNX1(22.0%),TP53(22.0%),DNMT3A(22.0%),NPM1(22.0%),IDH1/2(18.6%),CEBPA(15.3%),KMT2A(18.6%),NRAS(13.6%),TET2(13.6%),ASXL1(6.8%), andEZH2(0%). In the FLT3 positive AML cohort, six patients were registered and one achieved remission by quizartinib after progression on gilteritinib. Conclusions:The evaluation of F1H for its use in HM-SCREEN-Japan 01 facilitates the analysis of leukemia-associated genes that can be used as therapeutic targets, which have rarely been identified in AML thus far. Figure Disclosures Shibayama: Shionogi:Research Funding;Taiho:Research Funding;Eisai:Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding;Celgene:Membership on an entity's Board of Directors or advisory committees, Research Funding;Ono:Honoraria, Research Funding;Takeda:Honoraria, Research Funding;Merck Sharp & Dohme:Research Funding;Sumitomo Dainippon:Honoraria, Research Funding;Nippon Shinyaku:Honoraria, Research Funding;Daiichi Sankyo:Honoraria;Novartis:Honoraria, Research Funding;Janssen:Honoraria, Research Funding;Chugai:Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding;Kyowa Kirin:Honoraria;Otsuka:Honoraria;Bristol-Myers Squibb:Honoraria;Pfizer:Honoraria;Fujimoto:Honoraria;AbbVie:Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding;AstraZeneca:Honoraria, Membership on an entity's Board of Directors or advisory committees;Sanofi:Honoraria;Mundi Pharma:Honoraria;Teijin:Research Funding;Astellas:Research Funding.Yamauchi:Chugai:Honoraria;Pfizer:Honoraria, Research Funding;Ono Pharmaceutical:Honoraria;Otsuka:Research Funding;Astellas:Research Funding;Abbie:Research Funding;Solasia Pharma:Research Funding;Daiichi Sankyo:Research Funding.Gotoh:Alexion pharmaceuticals:Research Funding;Eisai:Honoraria;Ono Pharmaceutical:Honoraria;Taiho pharmaceutical:Honoraria;Takeda pharmaceutical:Honoraria;Nippon Shinyaku:Honoraria;Chugai:Honoraria;Novartis:Research Funding.Yamamoto:Zenyaku:Research Funding;Yakult:Research Funding;Takeda:Consultancy, Honoraria, Research Funding;SymBio:Research Funding;Solasia Pharma:Research Funding;Stemline Therapeutics:Consultancy;Sumitomo Dainippon:Honoraria;Sanofi:Honoraria;Pfizer:Honoraria;Otsuka:Consultancy, Honoraria, Research Funding;Ono:Consultancy, Honoraria, Research Funding;Novartis:Honoraria, Research Funding;Nippon Shinyaku:Honoraria, Research Funding;Mundipharma:Consultancy, Honoraria, Research Funding;MSD:Consultancy, Honoraria, Research Funding;Mochida:Honoraria;Meiji Seika Pharma:Consultancy, Honoraria;Kyowa Kirin:Honoraria;Janssen:Honoraria;Gilead Sciences:Research Funding;IQIVA/Incyte:Research Funding;HUYA:Consultancy;IQIVA/HUYA:Honoraria;Daiichi Sankyo:Consultancy;Eisai:Consultancy, Honoraria, Research Funding;Chugai:Consultancy, Honoraria, Research Funding;Celgene:Consultancy, Honoraria, Research Funding;Bristol-Myers Squibb:Honoraria;Bayer:Research Funding;Astra-Zeneca:Consultancy, Research Funding;AbbVie:Consultancy, Honoraria, Research Funding;Aichi Cancer Center:Current Employment.Fujishima:Pfizer:Speakers Bureau.Takahashi:Bristol-Myers Squibb Company:Honoraria;Novartis Pharma KK:Honoraria, Research Funding;Pfizer Japan Inc.:Honoraria, Research Funding.Usuki:Novartis:Research Funding, Speakers Bureau;Chugai:Research Funding;Apellis:Research Funding;Alexion:Research Funding, Speakers Bureau.ONO:TAIHO PHARMACEUTICAL CO., LTD.:Research Funding;Mundipharma K.K.:Honoraria;DAIICHI SANKYO COMPANY, LIMITED.:Honoraria;Janssen Pharmaceutical K.K:Honoraria;Eisai Co., Ltd.:Honoraria;Astellas Pharma Inc.:Honoraria;Takeda Pharmaceutical Company Limited.:Honoraria;ONO PHARMACEUTICAL CO., LTD.:Honoraria, Research Funding;Otsuka Pharmaceutical Co., Ltd.:Honoraria;Pfizer Japan Inc.:Honoraria;Bristol-Myers Squibb Company:Honoraria;Novartis Pharma KK:Honoraria;Chugai Pharmaceutical Co., Ltd.:Honoraria, Research Funding;Kyowa Kirin Co., Ltd.:Honoraria, Research Funding;Celgene:Honoraria, Research Funding.Kuroda:Astellas Pharma:Honoraria, Research Funding;Sanofi:Consultancy, Honoraria, Research Funding;Daiichi Sankyo:Honoraria, Research Funding;Shionogi:Research Funding;Nippon Shinyaku:Honoraria, Research Funding;Fujimoto Pharmaceutical:Honoraria, Research Funding;Sysmex:Research Funding;Eisai:Honoraria, Research Funding;Ono Pharmaceutical:Honoraria, Research Funding;Abbvie:Consultancy, Honoraria;MSD:Research Funding;Celgene:Consultancy, Honoraria, Research Funding;Takeda:Honoraria, Research Funding;Dainippon Sumitomo Pharma:Honoraria, Research Funding;Chugai Pharmaceutical:Honoraria, Research Funding;Bristol-MyersSquibb:Consultancy, Honoraria, Research Funding;Janssen Pharmaceutical K.K:Consultancy;Asahi Kasei:Research Funding;Taiho Pharmaceutical:Research Funding;Kyowa Kirin:Honoraria, Research Funding;Otsuka Pharmaceutical:Honoraria, Research Funding;Pfizer:Honoraria, Research Funding.Izutsu:Sanofi:Research Funding;Symbio:Research Funding;Solasia:Research Funding;Janssen:Research Funding;Yakult:Research Funding;HUYA Japan:Research Funding;Abbvie pharmaceuticals:Research Funding;Incyte:Research Funding;Eisai:Research Funding;AstraZeneca:Research Funding;Daiichi Sankyo:Research Funding;Bayer pharmaceuticals:Research Funding;Ono Pharmaceutical:Research Funding;Novartis:Research Funding;Chugai:Research Funding;Celgene:Research Funding.Minami:Bristol-Myers Squibb Company:Honoraria;Pfizer Japan Inc.:Honoraria;Novartis Pharma KK:Honoraria;Takeda:Honoraria.

Introduction: ABL tyrosine kinase inhibitors (TKIs) improved outcomes for patients with chronic myeloid leukemia (CML) and Philadelphia chromosome (Ph)-positive leukemia. However, ABL TKIs do not eliminate the leukemia stem cells (LSCs) in the bone marrow, which may represent the most important event in leukemia relapse after TKI discontinuation. Bone marrow is also considered a tissue with limited oxygen supply. Therefore, new approach against leukemia stem cells, which is presented in bone marrow under hypoxia, may improve the outcome of CML patients. Nicotinamide phosphoribosyl transferase (NAMPT) is the rate limiting enzyme of the primary pathway for maintaining cellular NAD+ and that regulates intracellular adenosine triphosphate (ATP) levels in mammalian cells. It has been reported that NAMPT expression is upregulated in several human cancers. Materials and methods: In this study, we established ABL TKI resistantin vitrocell line models (K562 imatinib-R, K562 nilotinib-R, K562 ponatinib-R and Ba/F3 T315I) and used Ph-positive leukemia cell lines. We also investigated whether NAMPT inhibitor could suppress Ph-positive leukemia cells including T315I mutation and ABL TKI resistant under hypoxic condition. Results: In chemical library screen of compounds, NAMPT inhibitor, CHS828 is selected the candidate drug for ABL TKI resistant cells under hypoxic condition. Drug repositioning and repurposing can be an important part of any drug discovery. Therefore, we examined NAMPT efficacy by using Ph-positive leukemia cell lines. We first investigated the NAMPT expression by microarray gene expression data from the online Gene Expression Omnibus (GEO). Gene expression of NAMPT is increased in CML patients compared to normal samples from the public microarray datasets of GSE13159. Protein expression of NAMPT is found in Ph-positive leukemia cell lines including ABL TKI resistant cells. In hypoxia, gene expression of NAMPT was increased in Ph-positive cells compare to normoxic condition. We next examined efficacy of NAMPT inhibitor, CHS828 in Ph-positive leukemia cell lines. We found that CHS828 treatment for 72 h decreased cell viability of Ph-positive cell lines in a dose dependent manner. We also found that CHS828 inhibited the proliferation of ABL TKI resistant cells (K562 imatinib-R, K562 nilotinib-R, K562 ponatinib-R) and T315I mutant Ba/F3 cells under hypoxic condition. The rate of cell cycle progression was delayed and cells were blocked in G2/M phase. Nuclear factor-kappaB (NF-kB) is also implicated in cancer development. CHS828 inhibited constitutive NF-kB activity in the time and dose dependent manner. Intracellular ATP, which is the most important source of energy for cellular reactions, was drastically decreased after CHS828 treatment. NAD+ plays a vital role in diverse cellular processes that govern human health and disease. Intracellular NAD+ was decreased after CHS828 treatment. The wound healing effect was evaluated at 0, 24, 48, and 72 h by using NIH3T3 cells. In wound healing results, CHS828 treatment inhibited cellular migration of NIH3T3 cells. We next investigated the efficacy of ABL TKI and CHS828 against Ph-positive leukemia cell lines. ABL TKI and CHS828 treatment induced cellular growth inhibition compared with each drug alone. Caspase 3/7 activity was also increased after ABL TKIs and CHS828 treatment. ABL TKI and CHS828 reduced the colony formation ability of Ph-positive cells under hypoxic condition. Thein vivoefficacies of one of ABL TKI, ponatinib and CHS828 were evaluated in a mouse xenograft model. Ponatinib and CHS828 inhibited the growth of T315I mutant Ba/F3 cellsin vivomore than the control vehicle. We also found that co-treatment with ponatinib and CHS828 increased mouse survival. Combination treatment with ponatinib and CHS828 was also well tolerated, with no animal deaths in the treated mice. Conclusion: The results of our study indicate that the ABL TKI and CHS828 may be a powerful strategy against Ph-positive cells including ABL TKI resistant cells and provide the promising clinical relevance as a candidate drug for treatment of CML stem cells of the bone marrow microenvironment under hypoxic condition. Disclosures No relevant conflicts of interest to declare.

A 62-year-old man with asthma presented with a 1-month history of wheezing and exertional dyspnea. Although the wheezing symptoms disappeared after systemic corticosteroid therapy, the exertional dyspnea and hypoxemia did not improve. A diagnosis of intravascular large B-cell lymphoma (IVLBCL) with pulmonary involvement was suspected because of the increased serum lactic dehydrogenase (LDH) and soluble interleukin-2 receptor (sIL-2R) level, increased alveolar-arterial oxygen difference (AaDO2), decreased pulmonary diffusing capacity for carbon monoxide (DLCO) and scintigraphic, computed tomography (CT) and 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET)-CT findings. The patient was diagnosed as having IVLBCL with pulmonary involvement based on a pathological analysis of a random skin biopsy and a transbronchial lung biopsy. IVLBCL should be considered in patients with symptoms of asthma that are refractory to corticosteroid treatment.

A 70-year-old woman was diagnosed with chronic rheumatoid arthritis and treated with methotrexate and prednisolone. She visited our hospital to determine the cause of her continuous fatigue and fever for the past three weeks. She consumed no food orally and was provided antibiotics because free air was found on computed tomography (CT). Intraperitoneal small lymphadenopathy and swelling of both adrenal glands was also found on CT, and MTX-associated lymphoproliferative disorder (MTX-LPD) was suspected. Am adrenal gland biopsy showed diffuse large B-cell lymphoma (DLBCL) associated with MTX-LPD. The causes of gastrointestinal perforation with collagen diseases have been reported to be functional gastrointestinal disorders with collagen diseases like amyloidosis, gastrointestinal infections in immunocompromised patients, and side effects of medication, such as steroids or NSAIDs and MTX. MTX-LPD is an uncommon side effect of methotrexate. To ensure its appropriate diagnosis and treatment, it is important to improve the degree of recognition of MTX-LPD, and a prompt response is needed.

Neurological symptoms induced by the infiltration of malignant lymphoma into the nervous systems are subsumed under the term neurolymphomatosis (NL). Here, we report the case of a 30-year-old Japanese man with primary testicular lymphoma complicated, as seen in various neurological findings, by secondary NL prior to testicular swelling. Painless right scrotal enlargement was noticed more than 1 month after the appearance of neurological complications such as right upper extremity numbness, dysarthria, facial palsy, and diplopia. Proactive investigation and biopsies of extranodal sites at high risk of central nervous system infiltration of malignant lymphoma, such as the testes, should be considered when secondary NL is suspected based on imaging findings.

Objective There are currently two representative diagnostic criteria for essential thrombocythemia (ET), the 2014 British Committee for Standards in Hematology Guidelines (BCSH) criteria and the 2016 World Health Organization (WHO) criteria. We compare and discuss the advantages and disadvantages of the two criteria. Method We applied the two criteria to 403 patients with thrombocytosis and suspected myeloproliferative neoplasms (MPN) and compared patient populations. Results The BCSH criteria diagnosed ET in 279 patients (BCSH-ET) whereas the WHO criteria diagnosed ET in 203 patients (WHO-ET). There were 83 patients diagnosable only by the BCSH criteria (BCSH-only-ET), of which under the WHO classification, 69 patients fell under the category of MPN, unclassifiable (MPN-u), 12 patients were PMF, prefibrotic/early stage (prePMF), and two patients were polycythemia vera. Patient characteristics such as age, hemoglobin, hematocrit, platelet counts, lactate dehydrogenase levels, JAK2V617F allele burdens, prevalence of myelofibrosis and splenomegaly, and frequencies of thrombotic events and treatment did not differ between WHO-ET and BCSH-only-ET, but BCSH-only-ET patients showed higher WBC counts and higher JAK2V617F mutation frequencies. Conclusion The BCSH criteria diagnosed ET in a broader range of patients encompassing a significant number of patients who would otherwise be diagnosed as prePMF or MPN-u. This article is protected by copyright. All rights reserved.

Acquired hemophilia is a rare bleeding diathesis caused by autoantibodies against clotting factor VIII. Many cases are associated with autoimmune disease, malignancy and an elderly status. Acquired hemophilia is very rare, with a reported annual incidence of 1.48/million/y. However, it is necessary to consider this rare disease when encountering bleeding of unknown cause in elderly patients. An 84-year-old woman was referred to our hospital with subcutaneous bleeding and anemia. The patient had severe anemia and a prolonged activated partial prothrombin time (APTT). Despite the administration of red blood cell transfusions, the decline in hemoglobin continued. Since the activity of coagulation factor VIII was1%, and the level of inhibitor against coagulation factor VIII (509 BU/ml) was5 BU/ml, the patient was diagnosed with acquired hemophilia. No underlying diseases were found, and we concluded that this case was idiopathic. Although she was treated with prednisolone at a dose of 40 mg per day, the bleeding tendency did not improve. Therefore, she was given activated prothrombin complex concentrates (APCC) for four days. The subcutaneous bleeding and Hb decline stopped, and the dose of prednisolone was gradually reduced. The patient's clotting function and clinical course were satisfactory, and she was discharged on the 64th day. An early diagnosis and optimal treatment are critical for treating acquired hemophilia. The development of a bleeding tendency related to the appearance of coagulation factor VIII inhibitor is serious in many patients. Therefore, recognizing this disease and providing prompt management are necessary.

Exophiala dermatitidis infections in patients with hematological malignancies are very rare. Our patient had a blood stream infection caused by E. dermatitidis following the second umbilical cord blood transplantation (UCBT) after graft failure during the first UCBT. To our knowledge, this is the first report describing a breakthrough fungal infection caused by E. dermatitidis during the prophylactic administration of micafungin (MCFG). Therefore, MCFG-treated patients should be monitored for breakthrough E. dermatitidis infection during hematopoietic stem cell transplantation.

Objective: The use of tyrosine kinase inhibitors led to an improvement in the prognoses of patients with chronic myeloid leukemia (CML). The aims of this study were to investigate the efficacy and safety of dasatinib in Japanese patients and to explore the factors that affect the achievement of molecular responses. Methods: The primary endpoint was a major molecular response (MMR) by 12 months. The halving time for BCR-ABL1 transcripts was calculated using transcript levels. Results: Thirty-two patients with chronic-phase CML (CML-CP) were enrolled and 30 received 100 mg dasatinib once daily. At 24 months of follow-up, 21 (72%) and 24 (83%) patients achieved an MMR by 12 and 24 months, respectively; the rates of a deep molecular response (DMR) by 12 and 24 months were 48 and 59%, respectively. A shorter halving time of BCR-ABL1 transcripts (≤10.6 days) accurately predicted both an MMR and a DMR. The incidence of pleural effusion was 50%. Our study reconfirmed the efficacy and safety of dasatinib treatment in Japanese patients with newly diagnosed CML-CP. In addition, the usefulness of the halving time of BCR-ABL1 transcripts was validated. Conclusion: These data emphasize the significance of an early treatment response in achieving a DMR during dasatinib therapy.

Objectives To investigate the intramuscular changes on sonographic elastography (SE) after low-level static contraction of the masseter muscle, and to clarify the relationship with the total hardness and edematous change. Study design Ten healthy volunteers performed sustained bilateral biting at 20% of maximal voluntary contraction for 10 min. The SE and magnetic resonance (MR) scans of the masseter muscles were performed before, immediately after, and 10 min after exercise. The masseter muscle elasticity index (MEI) ratio, muscle thickness, and intramuscular soft and hard areas distribution were evaluated on SE images. The signal to noise ratio (SNR), indicating the water content, was measured on MR images. Results The soft area ratio showed significant correlations with the water content expressed as SNR. The hard area ratio showed significant correlations with the total muscle hardness expressed as the MEI ratio. Conclusion Intramuscular soft and hard areas could be used both clinically and experimentally.

The purpose of this study was to clarify, by use of sonographic elastography, the changes in elasticity of the masseter muscle after low-level continuous contraction by healthy volunteers. The reproducibility of the elasticity index (EI) was verified by using a scoring phantom for elastography. The EI of the masseter muscle was measured for 10 healthy volunteers before, immediately after, and 10 min after static contraction at 20 % of the maximum force for 10 min. The masseter muscle thicknesses were also measured at these times as a surrogate index of muscle edema. The reproducibility of the EI measurements was sufficient for clinical use. The elasticity expressed by the EI increased after low-level contraction compared with that before contraction and changed similarly to the thickness along the time course of the experiment. Low-level static contraction increased the elasticity and thickness of the masseter muscle. A potential relationship may exist between elasticity and edematous change in the masseter muscle.

Transfusion is believed to be the main cause of iron overload in Japan. A nationwide survey on post-transfusional iron overload subsequently led to the establishment of guidelines for iron chelation therapy in this country. To date, however, detailed clinical information on the entire iron overload population in Japan has not been fully investigated. In the present study, we obtained and studied detailed clinical information on the iron overload patient population in Japan. Of 1109 iron overload cases, 93.1% were considered to have occurred post-transfusion. There were, however, 76 cases of iron overload of unknown origin, which suggest that many clinicians in Japan may encounter some difficulty in correctly diagnosing and treating iron overload. Further clinical data were obtained for 32 cases of iron overload of unknown origin; median of serum ferritin was 1860.5 ng/mL. As occurs in post-transfusional iron overload, liver dysfunction was found to be as high as 95.7% when serum ferritin levels exceeded 1000 ng/mL in these patients. Gene mutation analysis of the iron metabolism-related genes in 27 cases of iron overload with unknown etiology revealed mutations in the gene coding hemojuvelin, transferrin receptor 2, and ferroportin; this indicates that although rare, hereditary hemochromatosis does occur in Japan.

Early intracranial hemorrhage (eICH) is a potentially fatal complication of acute leukemia. We analyzed risk factors for eICH in patients with de novo acute leukemia. Ninety-one de novo acute leukemia patients at our institution between September 2003 and June 2014 were included. Of the 91 patients, eight (8.8 %) and 83 were included in the eICH and non-eICH groups, respectively. Univariate analysis demonstrated that white blood cell (WBC) count (P = 0.018), fibrin–fibrinogen degradation product (FDP) level (P = 0.0075), co-occurrence of WBC ≥50,000/µl and FDP level >40 µg/ml (P

The aims were to investigate the relationship between the masseter muscle elasticity index (MEI) ratio obtained by sonographic elastography and the hardness measured by a hardness meter in healthy volunteers, and to clarify the characteristics of the masseter muscle hardness in temporomandibular disorder (TMD) patients with myofascial pain. Sonographic elastography images were obtained using a LOGIQ E9 (GE Healthcare), and the MEI ratios were calculated using Elasto Q software. The relationship between the MEI ratio and the masseter muscle hardness measured using a hardness meter was examined in 35 healthy volunteers. The MEI ratio in 8 TMD patients with myofascial pain was compared with that of the healthy volunteers. The MEI ratio was significantly correlated with the masseter muscle hardness. There was a significant difference between the MEI ratios of the symptomatic and asymptomatic sides in the TMD patients with myofascial pain. The MEI ratio of the symptomatic side in the TMD patients was larger than that on the right side of the healthy volunteers. Sonographic elastography can be used to express the muscle hardness. It can be selected as a modality for showing the features of muscles with pain.

Pregnancy with paroxysmal nocturnal hemoglobinuria (PNH) is associated with significant risk of complications, such as life-threatening thrombosis. Recently, eculizumab has come into clinical use and revolutionized the treatment of PNH. However, clinical information regarding eculizumab use for PNH during pregnancy is limited. The present report describes pregnancies with PNH treated with eculizumab that were registered with the Japan PNH study group and reviews the literature. In case 1, the patient received eculizumab throughout pregnancy and delivered a healthy neonate at term, although breakthrough hemolysis occurred at 20 weeks of gestation. In case 2, the patient discontinued eculizumab before pregnancy and developed preeclampsia at 27 weeks of gestation. She received eculizumab and delivered a preterm, but healthy, neonate by cesarean section. In case 3, the patient received eculizumab from 18 weeks of gestation and delivered a healthy neonate at term without any complications. Reports of 11 pregnant women treated with eculizumab were identified in the literature. Of 14 pregnancies, including our own cases, breakthrough hemolysis and preeclampsia occurred in five and two cases, respectively. There were no thrombotic complications, maternal or neonatal deaths, or fetal structural abnormalities. Thus, eculizumab appears to be safe and effective for managing PNH during pregnancy.

A 49-year-old Japanese female was initially diagnosed as having monoclonal gammopathy of undetermined significance in June 1993 (IgG lambda: 3,120 mg/dl). Four years later, she developed AL amyloidosis complicated by nephrotic syndrome and renal failure. Before receiving 5 courses of MP therapy (melphalan plus prednisolone), her serum IgG level had decreased in accordance with the appearance of nephrotic syndrome, which led to the leakage of serum immunoglobulin into the urine. After the discontinuation of the MP therapy, hypogammaglobulinemia has been kept over 24 months, though she still shows a leakage of 4-5 g/day of serum protein, including IgG into the urine. There were no signs of the progression of amyloidosis or renal failure, resulting in a good clinical performance status. Hypogammaglobulinemia due to nephrotic syndrome may have prevented the progression of AL amyloidosis in this case.

A 75-year-old woman was admitted to the hospital because of intensifying severe abdominal pain. Physical examination at admission showed tenderness with Blumberg's sign of the right upper quadrant. Abdominal CT revealed cholecystolithiasis and swellings of the gallbladder and right kidney. Blood laboratory studies showed a leucocyte count of 14, 800/mm3 and blood sugar level of 746mg/dl. An emergency operation was carried out with the diagnosis of peritonitis. During laparotomy, there were swollen gallbladder with several stones and pyonephrosis of the right kidney. Cholecystectomy and right nephrectomy were performed. The resected material revealed a 30×35mm, irregular and elevated lesion extending from the body to fundus of the gallbladder and a change in colour to dark-red of most part of the right kidney. Histopathologically, the elevated lesion of the gallbladder was diagnosed as papillary adenocarcinoma and a transitional cell carcinoma of the ureter covering from a portion near the surgical stump to the renal pelvis was demonstrated. A diagnosis of synchronous double cancer of the ureter and gallbladder was made. In the present case, dysfunction of the ureter due to the ureteral carcinoma was considered to have caused pyonephrosis, which led to diffuse peritonitis.

Leiomyosarcoma rarely occurs in the small intestine. It is said that the disease can more easily cause perforation than other malignancies because of its strong tendency to necrose internally. Recently we experienced a case of leiomyosarcoma of the jejunum causing perforation of the tumor with diffuse peritonitis. A 79-year-old man was referred to the hospital with a suspicion of peritonitis who consulted another hospital because of an abrupt onset of severe abdominal pain. On admission the abdomen was board-like and muscle guarding in the entire abdomen was present. Plain chest X-ray film revealed free air. Abdominal ultrasonography and CT visualized a hen egg sized tumor in the left upper quadrant. The case was diagnosed as diffuse peritonitis due to perforation of the gastrointestinal tract and an emergency laparotomy was performed. It was revealed that a part of an extramurally growing tumor arised in the jejunum perforated. The tumor was 55×36×34mm in size, and many peritoneal disseminations were also seen. Partial resection of the jejunum by about 30 cm with Roux Y anastomosis was performed. The tumor was diagnosed as leiomyosarcoma histopathologically. The patient was discharged from the hospital on 47th postoperative day.