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Pleomorphic mantle cell lymphoma (PMCL) can closely mimic diffuse large B-cell lymphoma (DLBCL) morphologically, and expression of CD5 and cyclin D1 is helpful for differential diagnosis. To date, no cases of CD5/cyclin D1 double-negative PMCL have been reported. Four cases of B-cell lymphoma with an immunophenotype of CD5(-) cyclin D1(-) SOX11(+) and morphologic features compatible with DLBCL were included. Two were previously identified, and the other 2 were screened from 500 cases of B-cell lymphoma. We analyzed their clinicopathologic, immunophenotypic, genetic, and gene expression features. Cases of cyclin D1-positive PMCL, cyclin D1-negative PMCL, germinal center B-cell (GCB) DLBCL, and activated B cell (ABC) DLBCL were also studied for comparison. Similar to other PMCL cases, these 4 patients were mainly elderly male individuals with an aggressive clinical course. None of these tumors had detectable translocations involving CCND1, CCND2, CCND3, CCNE1, CCNE2, MYC, BCL2, or BCL6. The genome-wide copy number profile of these 4 cases was similar to that of cyclin D1-negative PMCL. None of these tumors had high expression of cyclin D1, cyclin D2, or cyclin D3. Similar to cyclin D1-negative PMCL, these cases had higher expression of cyclin E1 and cyclin E2 compared with cyclin D1-positive PMCL. The gene expression pattern of these tumors was also similar to that of cyclin D1-negative PMCL. Here we report for the first time 4 cases of CD5/cyclin D1 double-negative PMCL. SOX11 positivity is useful to identify these rare tumors, and further genetic and gene expression analysis can be used to confirm the diagnosis.

There are different BCR-ABL1 fusion genes that are translated into proteins that are different from each other, yet all leukemogenic, causing chronic myeloid leukemia (CML) or acute lymphoblastic leukemia. Their frequency has never been systematically investigated. In a series of 45503 newly diagnosed CML patients reported from 45 countries, it was found that the proportion of e13a2 (also known as b2a2) and of e14a2 (also known as b3a2), including the cases co-expressing e14a2 and e13a2, was 37.9% and 62.1%, respectively. The proportion of these two transcripts was correlated with gender, e13a2 being more frequent in males (39.2%) than in females (36.2%), was correlated with age, decreasing from 39.6% in children and adolescents down to 31.6% in patients ≥ 80 years old, and was not constant worldwide. Other, rare transcripts were reported in 666/34561 patients (1.93%). The proportion of rare transcripts was associatedwith gender (2.27% in females and 1.69% in males) and with age (from 1.79% in children and adolescents up to 3.84% in patients ≥ 80 years old). These data show that the differences in proportion are not by chance. This is important, as the transcript type is a variable that is suspected to be of prognostic importance for response to treatment, outcome of treatment, and rate of treatment-free remission.

Clinical sequencing across a large prospective cohort of patients with myelodysplasic syndrome uncovers distinct associations between the mono- and biallelic states ofTP53and clinical presentation Tumor protein p53 (TP53) is the most frequently mutated gene in cancer(1,2). In patients with myelodysplastic syndromes (MDS),TP53mutations are associated with high-risk disease(3,4), rapid transformation to acute myeloid leukemia (AML)(5), resistance to conventional therapies(6-8)and dismal outcomes(9). Consistent with the tumor-suppressive role ofTP53, patients harbor both mono- and biallelic mutations(10). However, the biological and clinical implications ofTP53allelic state have not been fully investigated in MDS or any other cancer type. We analyzed 3,324 patients with MDS forTP53mutations and allelic imbalances and delineated two subsets of patients with distinct phenotypes and outcomes. One-third ofTP53-mutated patients had monoallelic mutations whereas two-thirds had multiple hits (multi-hit) consistent with biallelic targeting. Established associations with complex karyotype, few co-occurring mutations, high-risk presentation and poor outcomes were specific to multi-hit patients only.TP53multi-hit state predicted risk of death and leukemic transformation independently of the Revised International Prognostic Scoring System (IPSS-R)(11). Surprisingly, monoallelic patients did not differ fromTP53wild-type patients in outcomes and response to therapy. This study shows that consideration ofTP53allelic state is critical for diagnostic and prognostic precision in MDS as well as in future correlative studies of treatment response.

Jie Jin,1,2 Rumiko Okamoto,3 Sung-Soo Yoon,4 Lee-Yung Shih,5 Jun Zhu,6 Ting Liu,7 Xiaonan Hong,8 Lixia Pei,9 Brendan Rooney,10 Helgi van de Velde,11 Huiqiang Huang12 1Department of Hematology, The First Affiliated Hospital of Zhejiang University College of Medicine, Hangzhou, Zhejiang, China; 2Key Laboratory of Hematologic Malignancies, Diagnosis and Treatment, Hangzhou, Zhejiang, China; 3Department of Chemotherapy, Tokyo Metropolitan Cancer and Infectious Diseases Center, Komagome Hospital, Tokyo, Japan; 4Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Republic of Korea; 5Division of Hematology–Oncology, Chang Gung Memorial Hospital-Linkou, Chang Gung University, Taoyuan, Taiwan; 6Department of Lymphoma, Peking University Cancer Hospital & Institute, Beijing, China; 7Division of Hematology, Department of Internal Medicine, West China Hospital, Sichuan University, Chengdu, Sichuan, China; 8Lymphoma and GI Medical Oncology, Fudan University Shanghai Cancer Center, Shanghai, China; 9Janssen Research & Development, LLC, Raritan, NJ, USA; 10Janssen Research & Development, High Wycombe, Buckinghamshire, UK; 11Oncology Clinical Research, Millennium Pharmaceuticals, Inc., Boston, MA, USA; 12Department of Medical Oncology, Sun Yat-sen University Cancer Center, Guangzhou, Guangdong, China Introduction: This subgroup analysis of the LYM-3002 Phase III study (NCT00722137) investigated whether substituting bortezomib for vincristine in frontline R-CHOP (rituximab plus cyclophosphamide, doxorubicin, vincristine, and prednisone) therapy could improve outcomes in East Asian patients with newly diagnosed mantle-cell lymphoma (MCL). Materials and methods: A total of 121 East Asian patients from China, Taiwan, Japan, and the Republic of Korea with stage II–IV MCL who were ineligible or not considered for stem-cell transplantation were enrolled to six to eight 21-day cycles of R-CHOP or VR-CAP (R-CHOP with bortezomib replacing vincristine). Results: The primary end point was progression-free survival. After a median follow-up of 42.4 months, median progression-free survival in East Asian patients was 13.9 (R-CHOP) versus 28.6 (VR-CAP) months (HR 0.7, P=0.157; 43% improvement with VR-CAP). Secondary end points (R-CHOP vs VR-CAP), including complete response rate (47% vs 63%), duration of complete response (median 16.6 vs 46.7 months), and treatment-free interval (median 21 vs 46.5 months), were improved with VR-CAP. VR-CAP was associated with increased but manageable toxicity. The most frequent adverse events were hematologic toxicities. Conclusion: VR-CAP was effective in East Asian patients with newly diagnosed MCL, and could be considered for patients in whom stem-cell transplantation is not an option. Keywords: mantle-cell lymphoma, bortezomib, VR-CAP, R-CHOP

Leukemia accepted article preview online, 01 August 2016. doi:10.1038/leu.2016.212.

Acute promyelocytic leukemia (APL) is a subtype of myeloid leukemia characterized by differentiation block at the promyelocyte stage. Besides the presence of chromosomal rearrangement t(15;17), leading to the formation of PML-RARA (promyelocytic leukemia-retinoic acid receptor alpha) fusion, other genetic alterations have also been implicated in APL. Here, we performed comprehensive mutational analysis of primary and relapse APL to identify somatic alterations, which cooperate with PML-RARA in the pathogenesis of APL. We explored the mutational landscape using whole-exome (n=12) and subsequent targeted sequencing of 398 genes in 153 primary and 69 relapse APL. Both primary and relapse APL harbored an average of eight non-silent somatic mutations per exome. We observed recurrent alterations of FLT3, WT1, NRAS and KRAS in the newly diagnosed APL, whereas mutations in other genes commonly mutated in myeloid leukemia were rarely detected. The molecular signature of APL relapse was characterized by emergence of frequent mutations in PML and RARA genes. Our sequencing data also demonstrates incidence of loss-of-function mutations in previously unidentified genes, ARID1B and ARID1A, both of which encode for key components of the SWI/SNF complex. We show that knockdown of ARID1B in APL cell line, NB4, results in large-scale activation of gene expression and reduced in vitro differentiation potential.

Chronic myelomonocytic leukemia (CMML) is a clonal hematopoietic disorder with heterogeneous clinical, morphological and genetic characteristics. Clonal cytogenetic abnormalities are found in 20-30% of patients with CMML. Patients with low risk cytogenetic features (normal karyotype and isolated loss of Y chromosome) account for similar to 80% of CMML patients and often fall into the low risk categories of CMML prognostic scores. We hypothesized that single nucleotide polymorphism arrays (SNP-A) karyotyping could detect cryptic chromosomal alterations with prognostic impact in these subgroup of patients. SNP-A were performed at diagnosis in 128 CMML patients with low risk karyotypes or uninformative results for conventional G-banding cytogenetics (CC). Copy number alterations (CNAs) and regions of copy number neutral loss of heterozygosity (CNN-LOH) were detected in 67% of patients. Recurrent CNAs included gains in regions 8p12 and 21q22 as well as losses in 10q21.1 and 12p13.2. Interstitial CNN-LOHs were recurrently detected in the following regions: 4q24-4q35, 7q32.1-7q36.3, and 11q13.3-11q25. Statistical analysis showed that some of the alterations detected by SNP-A associated with the patients' outcome. A shortened overall survival (OS) and progression free survival (PFS) was observed in cases where the affected size of the genome (considering CNAs and CNN-LOHs) was >11 Mb. In addition, presence of interstitial CNN-LOH was predictive of poor OS. Presence of CNAs (>= 1) associated with poorer OS and PFS in the patients with myeloproliferative CMML. Overall, SNP-A analysis increased the diagnostic yield in patients with low risk cytogenetic features or uninformative CC and added prognostic value to this subset of patients. (C) 2015 Wiley Periodicals, Inc.

EED mutants impair polycomb repressive complex 2 in myelodysplastic syndrome and related neoplasms

c-KIT mutations have been described in core-binding factor (CBF) acute myeloid leukemia (AML) at diagnosis. The role of c-KIT mutations in the relapse of CBF-AML is not clear. The role of CSF1R mutation in the pathogenesis of AML remains to be determined. We analyzed receptor tyrosine kinases (RTKs) and Ras mutations on 154 children with AML. Also, we examined the paired diagnosis and relapse samples in CBF-AML. CBF-AML accounted for 27% (41/154). c-KIT mutations were detected in 41.5% of CBF-AML at diagnosis (6 in exon 8, 10 in exon 17 and 1 in both exons 8 and 17) , FLT3-TKD 2.7%, N-Ras mutations 7.3% and K-Ras mutations 4.9%. FLT3-LM and CSF1R mutations were not found in CBF-AML. The mutations of RTKs and Ras were mutually exclusive except for one patient who had both c-KIT and N-Ras mutations. Eight of the 41 CBF-AML patients relapsed; four patients retained the identical c-KIT mutation patterns as those at diagnosis, the remaining four without c-KIT mutations at diagnosis did not acquire c-KIT mutations at relapse. Our study showed that 54% of childhood CBF-AML had RTKs and/or Ras mutations; c-KIT but not CSF1R mutations play a role in the leukemogenesis of childhood CBF-AML.

Diffuse large B cell lymphoma (DLBCL) is the most common non-Hodgkin lymphoma. Age over 60 years is one of the five parameters of the International Prognostic Index (IPI), which is the most important clinical prognostic predictor in DLBCL. A previous study on German DLBCL patients over 60 years of age showed that immunoblastic morphology, but not germinal center B cell-like (GCB)/non-GCB subtype, correlated with short survival. We collected 174 DLBCL cases over 60 years of age in Taiwan and performed immunophenotyping and detection of Epstein-Barr virus (EBV)-encoded RNA (EBER) by in situ hybridization. Of the cases, 5.2 % were positive for CD5 and 5.7 % positive for EBER. Neither immunoblastic morphology nor GCB/non-GCB subtype correlated with survival. In univariate analysis, adverse prognostic factors included IPI ≥ 3 (P < 0.000001), B symptoms (P = 0.000075), bone marrow/peripheral blood involvement (P = 0.017), EBER positivity (P = 0.0013), and CD5 positivity (P = 0.016). In multivariate analysis, CD5 positivity was the only independent adverse prognostic factor (HR = 3.16; 95 % CI = 1.34–7.47; P = 0.0087) in addition to IPI ≥ 3 (HR = 3.07; 95 % CI = 1.84–5.11; P = 0.000018). Surprisingly, despite an overall 5.2 % incidence of central nervous system (CNS) relapse in our patients, none of the CD5+ cases experienced CNS relapse (P = 1.00). This is in stark contrast to the more frequent CNS relapse in Japanese CD5+ DLBCL patients. EBER positivity was associated with IPI ≥ 3 (P = 0.010), stage III–IV (P = 0.0082), and B symptoms (P = 0.011). In multivariate analysis, EBER positivity was not an independent adverse prognostic factor (P = 0.81), its effect being due likely to accompanying adverse clinical parameters.

A recent study identified a variant of the NUDT15 gene (rs116855232 C>T) associated with intolerance to thiopurine in Korean patients with Crohn's disease. This study prompted us to substantiate the finding in a Taiwanese population. Four hundred and four children with acute lymphoblastic leukemia (ALL), and 100 adults with chronic immune thrombocytopenic purpura or localized lymphoma having normal bone marrow were examined. Two candidate gene approaches, pyrosequencing for NUDT15 and TaqMan assay for thiopurine methyltransferase (TPMT) genotyping (rs1142345 A>G), were performed. We showed a risk allele frequency of NUDT15 of 11.6% in children with ALL and 15.5% in adults. By contrast, the risk allele frequency of TPMT was only 1.6% in children with ALL and 0.5% in adults. The high frequency of risk variant for NUDT15, but not the very low frequency of risk variant for TPMT, was closely associated with the intolerance to mercaptopurine in children with ALL in Taiwan, contrast to that of European descent. In regard to NUDT15 polymorphism, the maximal tolerable daily doses of mercaptopurine in homozygotes, heterozygotes and wild-type groups were 9.4 mg m-2, 30.7 mg m-2 and 44.1 mg m-2, respectively. The outcomes did not differ significantly among the different genotypes.

The roles of CEBPalpha mutations and its cooperating mutations in the relapse of acute myeloid leukemia (AML) are not clear. CEBPalpha mutations were analyzed on 149 patients with de novo AML at both diagnosis and relapse. Twenty-two patients (14.8%) had the mutations at diagnosis, two patients had N-terminal nonsense mutations alone, one had homozygous inframe duplication at the bZIP domain, and 19 patients had both N-terminal and bZIP mutations. Twenty patients relapsed with identical mutant patterns, two lost CEBPalpha mutations and none acquired the mutations at relapse. Cloning analysis showed that the N-terminal and C-terminal mutations occurred on separate cloned alleles and also on the same alleles in most of the diagnosis and relapse samples. Losing one of the two or more mutations on the same allele or acquiring the other mutation on the allele original carrying single mutation were observed not infrequently in the paired samples analyzed. Seven patients with CEBPalpha mutations had cooperating mutations with FLT3/ITD, FLT3/TKD or N-ras but not K-ras mutations. Our study showed that 91% of de novo AML harboring CEBPalpha mutations at diagnosis retained the identical mutant patterns but frequently changed in the allelic distribution at relapse.

Extensive clinical data have shown that lamivudine is an effective and safe drug for patients with chronic hepatitis B virus infection. No significant serious side effect has been reported. Four hundred and forty-eight patients with chronic hepatitis B, treated with lamivudine for more than 6 months, were closely monitored. Two patients developed acute myeloid leukaemia during or after lamivudine therapy. The first case developed acute myeloid leukaemia, 1 year after stopping lamivudine therapy, when A529T mutant HBV-DNA was still detectable. The second case achieved complete virological response but suffered from acute myeloid leukaemia during the ninth month of lamivudine treatment. D553N mutant hepatitis B virus was detected in granulocytes of her peripheral blood. Based on our lamivudine therapy data, the calculated incidence of acute myeloid leukaemia in patients during or after lamivudine therapy was higher in males and females than that of the general population. Whether lamivudine-selected viral mutations have enhanced activity/production of transcriptional transactivator and thereby increased the chance of leukaemic transformation of haematopoietic progenitor cells deserves further investigation.

Purpose: We analyzed Asp835 mutations of FLT3 on paired marrow samples at diagnosis and relapse from 120 adult patients with de novo acute myeloid leukemia (AML) to determine the role of FLT3 Asp835 mutation in the relapse of AML. Experimental Design: Asp835 mutation was analyzed by DNA PCR amplification of exon 20 of FLT3 gene followed by EcoRV digestion. All of the mutations were confirmed by sequence analysis. Mutant to wild-type allelic ratio was determined by Genescan analysis. The Expand Long Template PCR System was used to determine the allelic location of internal tandem duplication of FLT3 (FLT3/ITD) and Asp835 mutations. Results: Thirteen patients had Asp835 mutations at diagnosis, of them 8 lost the mutations at relapse, and the remaining 5 patients carrying Asp835 mutations at diagnosis relapsed with the identical mutation types. Another 6 patients acquired Asp835 mutations at relapse. Five samples harbored both FLT3/ITD and Asp835 mutations that were found on different alleles by cloning analysis in the 3 patients studied. There were no differences in WBC count, French-American-British subtype, percentage of marrow blasts, or circulating blasts between patients with and without Asp835 mutations, whereas the difference in the prevalence of Asp835 mutations among cytogenetic/molecular subgroups was statistically significant (P = 0.025). Conclusions: The present study showed that patients with AML had heterogeneous patterns of FLT3 Asp835 mutations, either acquisition or loss of the mutations at relapse. Asp835 mutant clone may develop as a secondary event in a subset of patients with AML.

Mutations of receptor tyrosine kinases are implicated in the constitutive activation and development of human hematologic malignancies. An internal tandem duplication (ITD) of the juxtamembrane domain-coding sequence of the FLT3 gene (FLT3-ITD) is found in 20-25% of adult acute myeloid leukemia (AML) and at a lower frequency in childhood AML. FLT3-ITD is associated with leukocytosis and a poor prognosis, especially in patients with normal karyotype. Recently, there have been three reports on point mutations at codon 835 of the FLT3 gene (D835 mutations) in adult AML. These mutations are located in the activation loop of the second tyrosine kinase domain (TKD) of FLT3 (FLT3-TKD). The clinical and prognostic relevance of the TKD mutations is less clear. To the best of our knowledge, there has been no report to describe FLT3-TKD mutations in childhood AML. In this pediatric series, FLT3-TKD mutations occurred in three of 91 patients (3.3%), an incidence significantly lower than that of FLT3-ITD (14 of 91 patients, 15.4%) in the same cohort of patients. None of them had both FLT3-TKD and FLT3-ITD mutations. Sequence analysis showed one each of D835 Y, D835 V, and D835 H. Of the three patients carrying FLT3-TKD, two had AML-M3 with one each of L- and V-type PML-RARalpha, and another one had AML-M2 with AML1-ETO. None of our patients with FLT3-TKD had leukocytosis at diagnosis. At bone marrow relapse, one of the four patients examined acquired FLT3-ITD mutation and none gained FLT3-TKD mutation.

Background We assessed the in vitro culture growth of erythroid progenitors [burst forming unit-erythroid (BFU-E)] and serum erythropoietin (EPO) levels in different groups of polycythaemia to determine the discriminative power in the differential diagnosis of polycythaemia. Methods We used the methylcellulose culture technique to study the growth of endogenous erythroid colonies (EECs) and EPO-dependent BFU-E from bone marrow (BM) and/or peripheral blood (PB) cells from 40 patients with polycythaemia vera (PV), 13 with secondary polycythaemia (SP), 19 with pure erythrocytosis (PE), five with PE and PV evolution later (PE-PV), and 12 with relative polycythaemia (RP). The serum EPO levels were measured by radioimmunoassay before treatment in 47 PV patients, 23 SP patients, 19 PE patients, five PE-PV patients and 16 RP patients, as well as after treatment in 38 PV patients, five PE-PV patients and 12 PE patients. Results The results of the erythroid progenitor culture assay showed that the numbers of EPO-dependent BFU-E in BM did not differ significantly among groups. The PB BFU-E were significantly higher in PV than in SP or PE, and no statistical differences were found among patients with SP, PE and RP. There was a correlation between BM BFU-E and PB BFU-E in the individual PV and PE patients. EECs were present in all BM and PB cultures of untreated and phlebotomy-treated PV and PE-PV patients, but were absent in 6 of 17 PV patients who had received cytotoxic therapy. EECs were not found in SP, PE and RP. PB could substitute for BM in the EEC or the BFU-E assay. Both pretreatment and post-treatment serum EPO levels of PV and PE-PV were similar, which were significantly lower than SP, PE or RP. The serum EPO levels in treated PV or PE-PV patients who had normal haematocrit values were not significantly different from those in untreated patients. In contrast, the phlebotomy-treated PE patients had significantly higher serum EPO values than untreated PE patients. In the differentiation between PV and PE, the sensitivity, specificity, positive predictive value and negative predictive value of post-treatment serum EPO levels at a cut-off level of 9 U L−1 were 74%, 92%, 97% and 52% respectively. The discriminative power of post-phlebotomy serum EPO levels was even higher with a positive predictive value of 80% and negative predictive value of 92% for the prediction of PV evolution in patients with pure erythrocytosis of unknown origin. Conclusion The present study showed that apart from EEC assay, the post-phlebotomy serum EPO level was a sensitive and specific parameter in the differential diagnosis of polycythaemia, in particular for the identification of PV among patients with unclassifiable polycythaemia.

A 31-year-old female with lymphoma was incidentally found to have a left retroperitoneal lymphangiomyomatosis (LAM). The tumor was proved by pathology and immunohistochemical study of the tissue specimen obtained by ultrasound-guided core needle biopsy. The characteristic sonographic, computed tomographic, magnetic resonance imaging, and positron emission tomographic (PET) features of this unusual lesion were described. It was managed conservatively and remained stable on 2-year follow-up study. LAM should be considered in the differential diagnoses in cases of a retroperitoneal solid mass with cystic components.

Acute promyelocytic leukemia (APL) is a subtype of myeloid leukemia characterized by differentiation block at the promyelocyte stage. Besides the presence of chromosomal rearrangement t(15;17), leading to the formation of PML-RARA (promyelocytic leukemia-retinoic acid receptor alpha) fusion, other genetic alterations have also been implicated in APL. Here, we performed comprehensive mutational analysis of primary and relapse APL to identify somatic alterations, which cooperate with PML-RARA in the pathogenesis of APL. We explored the mutational landscape using whole-exome (n=12) and subsequent targeted sequencing of 398 genes in 153 primary and 69 relapse APL. Both primary and relapse APL harbored an average of eight non-silent somatic mutations per exome. We observed recurrent alterations of FLT3, WT1, NRAS and KRAS in the newly diagnosed APL, whereas mutations in other genes commonly mutated in myeloid leukemia were rarely detected. The molecular signature of APL relapse was characterized by emergence of frequent mutations in PML and RARA genes. Our sequencing data also demonstrates incidence of loss-of-function mutations in previously unidentified genes, ARID1B and ARID1A, both of which encode for key components of the SWI/SNF complex. We show that knockdown of ARID1B in APL cell line, NB4, results in large-scale activation of gene expression and reduced in vitro differentiation potential.

Runt-related transcription factor 1 (RUNX1) is essential for normal hematopoiesis. RUNX1 mutations have rarely been reported in chronic myelomonocytic leukemia (CMML). We examined RUNX1 mutations in 81 patients with CMML at initial diagnosis. Mutational analysis was performed on bone marrow samples by direct sequencing of all reverse transcription PCR products amplified with three primer pairs that cover the entire coding sequences of RUNX1b. Thirty-two RUNX1 mutations were detected in 30 patients (37%); 23 mutants were located in the N-terminal part and 9 in the C-terminal region. The mutations consisted of 9 missense, 1 silent, 7 nonsense and 15 frameshift mutations. Two patients had biallelic heterozygous mutations. There was no difference in overall survival between patients with and without RUNX1 mutations, but a trend of higher risk of acute myeloid leukemia (AML) progression was observed in mutation-positive patients (16/30 vs 17/51, P=0.102), especially in patients with C-terminal mutations (P=0.023). The median time to AML progression was 6.8 months in patients with C-terminal mutations compared with 28.3 months in those without mutations (P=0.022). This study showed for the first time a high frequency of RUNX1 mutations in CMML. C-terminal mutations might be associated with a more frequent and rapid AML transformation.

Identification of marker genes including RUNX3 ( AML2 ) that discriminate between different myeloproliferative neoplasms and normal individuals

The fusion transcripts of MLL rearrangement [MLL(+)] in acute myeloid leukemia (AML) and their clinicohematologic correlation have not be well characterized in the previous studies. We used Southern blot analysis to screen MLL(+) in de novo AML. Reverse transcriptase-polymerase chain reaction was used to detect the common MLL fusion transcripts. cDNA panhandle PCR was used to identify infrequent or unknown MLL partner genes. MLL(+) was identified in 114 (98 adults) of 988 AML patients. MLL fusion transcripts comprised of 63 partial tandem duplication of MLL (MLL-PTD), 14 MLL-AF9, 9 MLL-AF10, 9 MLL-ELL, 8 MLL-AF6, 4 MLL-ENL and one each of MLL-AF1, MLL-AF4, MLL-MSF, MLL-LCX, MLL-LARG, MLL-SEPT6 and MLL-CBL. The frequency of MLL-PTD was 7.1% in adults and 0.9% in children (P

Transcription factor CCAAT/enhancer binding protein alpha(C/EBPα) is essential for granulocyte differentiation. CEBPα mutations have been described in 7–10% of adult patients with acute myeloid leukemia (AML) at initial diagnosis and conferred a favorable prognosis. CEBPα mutations in childhood AML has not been reported yet. In this study, we sought to assess the frequency of CEBPα mutration, its clinicohematologic correlation and to analyze the cooperating mutations, including FLT3 and N-ras mutations in childhood AML. CEBPα mutations were analyzed in 117 children (age one day to 17 years, median 5 years) with de novo AML. CEBPα mutation status was examined by performing DNA polymerase chain reaction (PCR) followed by direct sequencing for each PCR product. CEBPα mutations were detected in 7 (6.0%) of 117 patients. Of the 7 patients with CEBPα mutations, 4 had FAB subtype of M2, 2 M1 and 1 M4. All had intermediate cytogenetics and comprised 11.5% (7/61) of the intermediate cytogenetic risk group. Five of the 7 mutations occurred in both N-terminal part and bZIP domain, one had N-terminal frameshift mutation and the remaining one had an inframe insertion in the bZIP domain. Clonal analysis using expand long template PCR assay with a primer pair covering entire coding sequence was performed in all 5 patients carrying two different mutations. The results demonstrated that one had homozygous combined mutation and 4 had heterozygous biallelic mutations with the cloned alleles carrying single mutations at N-terminal or bZIP domain in the different alleles or harboring combined mutations in the same alleles. None of the remission marrow samples obtained from 5 patients who had CEBPα mutations at diagnosis carried the mutations. FLT3-ITD mutations were detected in 2 of the 7 patients with CEBPα mutations compared to 15 of the 109 patients without CEBPα mutations. None of the patients carrying CEBPα mutations had FLT3-TKD mutations. Two of the 7 CEBPα(+) patients also harbored N-ras mutations compared to 10 of the 110 patients without CEBPα mutations. Taken together, 4 of 7 CEBPα(+) patients had cooperating mutations including FLT3-ITD or N-ras as compared to 27 in 109 CEBPα(−) patients (P=0.081). There were no statistical differences in age, WBC count, LDH level, 5-year overall survival and event-free survival between patients with and without CEBPα mutations; similar results were obtained if we only analyzed patients with intermediate cytogenetics. The present data showed that the frequency of CEBPα mutations in our series of childhood AML was similar to that in adults. CEBPα mutations were frequently associated with FLT3-ITD or N-ras mutations supporting the two-hit hypothesis for the pathogenesis of AML.

The role of internal tandem duplication of fms-like tyrosine kinase 3 (FLT3/ITD), mutations at tyrosine kinase domain (FLT3/TKD) and N-ras mutations in the transformation of myelodysplastic syndrome (MDS) to AML was investigated in 82 MDS patients who later progressed to AML; 70 of them had paired marrow samples at diagnosis of MDS and AML available for comparative analysis. Five of the 82 patients had FLT3/ITD at presentation. Of the 70 paired samples, seven patients acquired FLT3/ITD during AML evolution. The incidence of FLT3/ITD at diagnosis of MDS was significantly lower than that at AML transformation (3/70 vs 10/70, P0.001). FLT3/ITD(+) patients progressed to AML more rapidly than FLT3/ITD(-) patients (2.5+/-0.5 vs 11.9+/-1.5 months, P=0.114). FLT3/ITD(+) patients had a significantly shorter survival than FLT3/ITD(-) patients (5.6+/-1.3 vs 18.0+/-1.7 months, P=0.0008). After AML transformation, FLT3/ITD was also associated with an adverse prognosis. One patient had FLT3/TKD mutation (D835Y) at both MDS and AML stages. Additional three acquired FLT3/TKD (one each with D835 H, D835F and I836S) at AML transformation. Five of the 70 matched samples had N-ras mutation at diagnosis of MDS compared to 15 at AML transformation (P0.001), one lost and 11 gained N-ras mutations at AML progression. Coexistence of FLT3/TKD and N-ras mutations was found in two AML samples. N-ras mutations had no prognostic impact either at the MDS or AML stage. Our results show that one-third of MDS patients acquire activating mutations of FLT3 or N-ras gene during AML evolution and FLT3/ITD predicts a poor outcome in MDS.

Analysis of internal tandem duplications of FLT3(FLT3/ITD) was performed on bone marrow samples obtained at diagnosis and relapse from 108 adult patients with de novo acute myeloid leukemia (AML) to determine the role of this mutation in leukemic relapse. Eighty-three patients had wild-type FLT3at both diagnosis and relapse, 16 had FLT3/ITD at both stages, whereas 8 had acquired the mutation and 1 had lost it at relapse. Using Genescan analysis, we found that FLT3/ITD levels at first relapse were significantly higher than those at diagnosis (mean ± SE, 40.5% ± 4.8% versus 17.9% ± 3.6%,P

Essential thrombocythemia (ET) is a heterogeneous disorder in which the clonality of hematopoiesis varies. The clinical significance of clonality status in ET remains to be determined. We used the human androgen receptor gene (HUMARA)–polymerase chain reaction assay to investigate X-chromosome inactivation patterns (XCIPs) and their value in predicting vascular complications in 89 female patients with ET. Fifty-four (68.4%) patients had a clonal pattern of XCIP, and 15 (19.0%) had a polyclonal pattern. The remaining 20 patients had either an ambiguous or a homozygous pattern of XCIP and were therefore excluded from further analysis. Patients with clonal XCIPs were older (P = .029) and were at greater risk for thrombosis (P = .007) than were those with polyclonal XCIPs. We did not find a correlation between the occurrence of hemorrhage and XCIP (P = .492). Advanced age was predictive of thrombosis and hemorrhage. Platelet count did not influence the risk for vascular complications. Hypertension was significantly correlated with thrombotic events (P = .002), whereas diabetes mellitus and hypercholesterolemia were of no predictive value. In a multivariate analysis, age was the significant predictor of thrombosis (P = .030); however, XCIPs (P = .083) and hypertension (P = .073) tended to predict thrombosis. Our results suggest that older patients who have clonal XCIPs or hypertension are at increased risk for thrombosis and should be monitored closely for this complication.

Acute promyelocytic leukemia (APL) is a hematopoietic malignant disease characterized by the chromosomal translocation t(15;17), resulting in the fusion of PML-RARA genes. We examined whether genomic alterations could be found other than t(15;17) using a sensitive technique in order to subcategorized this disease on the basis of genomic status. Thirty-three t(15;17) APL samples were analyzed with high-density single-nucleotide polymorphism microarray (50K SNP-chip) using the new algorithm AsCNAR (allele-specific copy-number analysis using anonymous references). Our analysis revealed that 10q (2 cases), 11p (3 cases) and 19q (1 case) regions were identified as loss of heterozygosity with normal copy number [we call this somatic uniparental disomy (UPD)] that could not be detected by karyotypic analysis. Nineteen samples (58%, Group A) did not have an obvious alteration. Fourteen samples (42%) showed either one or more genomic abnormalities: 6/14 of these samples (18%, Group B) had trisomy 8 either with or without duplication, deletion, and UPD; and 8/14 of these samples (24%, Group C) had abnormalities without trisomy 8. Interestingly, FLT3-ITD mutation (7/33 cases) was found only in Group A. These results suggest that the pathway of development of APL differs in each group; FLT3-ITD, trisomy 8 (probably c-Myc gene), and unknown factor(s) are involved in group A, B, and C, respectively. Here, we showed for the first time hidden abnormalities and novel disease-related genomic regions in t(15;17) APL. Our technique may become a routine, rapid, robust technique for subclassification of APL and to screen for novel therapeutic targets.

We used the in-vitro agar culture technique to monitor the granulopoiesis in 68 adult patients with ALL during the course of their disease. Bone marrow cells were cultured from 42 patients at diagnosis, 26 patients in relapse, 36 patients in early remission and 31 patients in full remission. The results of culture growth were characterized by sparse or no growth at diagnosis. No inhibition of normal CFU-C by leukemic cells was demonstrated by co-culture experiments. In relapsed marrows with blasts exceeding 60%, the culture results were identical to those at first presentation. The colonies grown in ALL cultures showed normal morphology with a normal granulocytic and monocytic differentiation. The colony-forming potential gradually increased following induction therapy, but there was no relationship between the CFU-C number and the percentage of blasts. The impaired granulopoiesis usually recovered once a remission was obtained and remained normal throughout the remission period. In some instances, cultures were performed within a short period prior to relapse or carried out more than one occasion during stable remission, wide fluctuations in CFU-C incidences were observed. Our study indicates that the CFU-C assay in ALL is useful for monitoring the in-vitro granulopoietic activity at various phases of the disease, but is of limited value in predicting the response to treatment as well as in determining the remission-relapse status.

Introduction Angiomyolipoma is a common benign renal tumor composed of thick-walled blood vessels, smooth muscle, and adipose tissue. It may be found incidentally during workup for suspected renal disease. Although angiomyolipoma may present as a palpable, tender renal mass with flank pain and gross or microscopic hematuria, many patients are asymptomatic. Erythrocytosis is an unusual presentation, and malignant transformation may be suspected. This report describes a rare case of a woman diagnosed with renal angiomyolipoma and polycythemia vera. The report discusses the differential diagnosis using erythropoietin, erythropoietin-receptor and Janus kinase 2. Case presentation A 79-year-old Chinese woman was diagnosed with erythrocytosis according to World Health Organization criteria. An upper left renal pole angiomyolipoma was successfully ablated after multiple phlebotomy treatments. Red cell count immediately returned to normal, but gradually increased after 4 months. Polycythemia vera was finally diagnosed by positive mutation of Janus kinase 2 and negative erythropoietin protein expression. Her clinical symptoms improved with regular phlebotomy and hydroxyurea treatment. Conclusion Concurrent occurence of angiomyolipoma and polycythemia vera is rare. Polycythemia vera can be easily missed. Polycythemia vera can be confirmed with high specificity and sensitivity by the acquired somatic mutation. Surgical intervention for this renal tumor should be avoided unless malignancy or renal cell carcinoma is suspected or to prevent spontaneous rupture of larger tumors.

Chromosome; Cytogenetics; Myelodysplastic syndromes Cromosoma; Citogenética; Síndromes mielodisplásicos Cromosoma; Citogenètica; Síndromes mielodisplàsics Half of the myelodysplastic syndromes (MDS) have normal karyotype by conventional banding analysis. The percentage of true normal karyotype cases can be reduced by 20–30% with the complementary application of genomic microarrays. We here present a multicenter collaborative study of 163 MDS cases with a normal karyotype (≥10 metaphases) at diagnosis. All cases were analyzed with the ThermoFisher® microarray (either SNP 6.0 or CytoScan HD) for the identification of both copy number alteration(CNA) and regions of homozygosity (ROH). Our series supports that 25 Mb cut-off as having the most prognostic impact, even after adjustment by IPSS-R. This study highlights the importance of microarrays in MDS patients, to detect CNAs and especially to detect acquired ROH which has demonstrated a high prognostic impact. 2017 SGR288 (GRC) and CERCA Programme/Generalitat de Catalunya. Fundació Internacional Josep Carreras; Italy Ministry of Health.