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•Successful pregnancies are possible among female alloHCT recipients, although birth rate is >6 times lower than in the general population.•Key factors increasing the chance of pregnancy were younger age at HCT, nonmalignant disease, no TBI or dose <8 Gy and RIC/NMA conditioning

There is no consensus on second allogeneic stem cell transplantation (alloSCT) indications in patients with hematologic malignancies relapsing after a first alloSCT. In historic publications, a very high non-relapse mortality (NRM) has been described, arguing against performing a second alloSCT. We analysed the outcome of 3356 second alloSCTs performed 2011–21 following a hematologic malignancy relapse. Outcomes at two years after second alloSCT were: NRM 22%, relapse incidence 50%, overall survival 38%, and progression-free survival 28%. Key risk factors for increased NRM were: older age, low performance score, high disease-risk-index, early relapse after the first alloSCT, unrelated/haploidentical donor, and GVHD before second alloSCT. Any type of GVHD after first alloSCT was also important risk factor for acute GVHD and chronic GVHD after second alloSCT. There was a preferential use of a different donor (80%) at second alloSCT from first alloSCT. However, in multivariate analysis, the use of the same alloSCT donor for second alloSCT vs. a different donor was not associated with any of the survival or GVHD endpoints. We show considerably improved outcome as compared to historic reports. These current data support a wider use of second alloSCT and provide risk factors for NRM that need to be considered.

Allogeneic hematopoietic cell transplantation (allo-HCT) remains the best consolidation strategy for acute myeloid leukemia (AML) with complex karyotype (CK). However, CK is a heterogenous and highly diverse entity. Numerical abnormalities have been associated with a controversial prognosis and AML with only multiple numerical abnormalities known as pure hyperdiploid karyotype (HDK) may have a distinct prognosis after allo-HCT compared to non-pure HDK CK AML. A total of 236 patients were identified within the EBMT registry as having HDK comprising 95 pure (pHDK) and 141 with other cytogenetic abnormalities (HDK+). The 2-year probability of leukemia-free survival (LFS) was 50% for pHDK and 31% for HDK+ (p= 0.003). The 2-year probability of overall survival (OS) was 57% for pHDK and 36% for HDK+ (p= 0.007). The 2-year cumulative incidence of relapse (RI) was 22% for pHDK and 44% for HDK+ (p= 0.001). The 2-year probability of graft-versus-host disease (GvHD)-free and relapse-free survival (GRFS) was 36% for pHDK and 21% for HDK+ (p= 0.01). On multivariate analysis, pHDK remained associated with significantly better LFS, OS and GRFS and lower RI (all p-values <0.004). pHDK AML constitutes probably a distinct cytogenetic entity from HDK+ or other non-hyperdiploid CK AML with better outcomes after allo-HCT.

The intensity of the conditioning regimen given before allogeneic hematopoietic cell transplantation (allo-HCT) can vary substantially. To confirm the ability of the recently developed transplant conditioning intensity (TCI) score to stratify the preparative regimens of allo-HCT, we used an independent and contemporary patient cohort of 4060 transplant recipients with acute myeloid leukemia meeting inclusion criteria from the discovery study (allo-HCT in first complete remission, matched donor), but who were allografted in a more recent period (2018–2021) and were one decade older (55–75 years, median 63.4 years), we assigned them to a TCI category (low n= 1934, 48%; intermediate n= 1948, 48%, high n= 178, 4%) according to the calculated TCI score ([1–2], [2.5–3.5], [4–6], respectively), and examined the validity of the TCI category in predicting early non-relapse mortality (NRM), 2-year NRM and relapse (REL). In the unadjusted comparison, the TCI index provided a significant risk stratification for d100 and d180 NRM, NRM and REL risk. In the multivariate analysis adjusted for significant variables, there was an independent association of TCI with early NRM, NRM and REL. In summary, we confirm in contemporary treated patients that TCI reflects the conditioning regimen related morbidity and anti-leukemic efficacy satisfactorily and across other established prognostic factors.

There is a high risk of GVHD and non-relapse mortality (NRM) after allogeneic stem cell transplantations (alloSCT) from unrelated donors. Prophylaxis with rabbit anti-thymocyte globulin (rATG) is standard in Europe but post-transplantation Cyclophosphamide (PTCy) is an emerging alternative. We analyzed outcomes of rATG (n= 7725) vs. PTCy (n= 1039) prophylaxis in adult patients with hematologic malignancies undergoing peripheral blood alloSCT from 10/10 antigen-matched unrelated donors (MUD) between January 2018 and June 2021 in the EBMT database. The provided P-values and hazard ratios (HR) are derived from multivariate analysis. Two years after alloSCT, NRM in the PTCy group was 12.1% vs. 16.4% in the rATG group; p= 0.016; HR 0.72. Relapse was less frequent after PTCy vs. rATG (22.8% vs. 26.6%; p= 0.046; HR 0.87). Overall survival after PTCy was higher (73.1% vs. 65.9%; p= 0.001, HR 0.82). Progression free survival was better after PTCy vs. rATG (64.9% vs. 57.2%; p< 0.001, HR 0.83). The incidence of chronic GVHD was lower after PTCy (28.4% vs. rATG 31.4%; p= 0.012; HR 0.77), whereas the incidence and severity of acute GVHD were not significantly different. GVHD-free relapse-free survival was significantly higher in the PTCy arm compared to the rATG arm (2 y incidence: 51% vs. 45%; HR: 0.86 [95% CI 0.75–0.99], p= 0.035). In the absence of evidence from randomized controlled trials, our findings support a preference for the use of PTCy in adult recipients of peripheral blood alloSCTs from MUD.

Older adults with acute myeloid leukemia (AML) refractory to initial or reinduction chemotherapy have a dismal prognosis if they do not undergo hematopoietic stem-cell transplantation (HCT). However, data assessing HCT outcomes from different donors are scarce. We evaluated results from a retrospective analysis on patients aged ≥70 years, with AML not in remission who received an allogeneic HCT from HLA-matched sibling donor (MSD), HLA-10/10 matched unrelated donor (MUD), or T-cell replete haploidentical (Haplo) donor, from 2010 to 2021, reported to the ALWP-EBMT database. A total of 360 patients (median age 72 years, range 70–79) were included in the analysis. Median follow-up for the entire population was 35.5 months. Donors were MSD (n= 58), 10/10 HLA-MUD (n= 228), and Haplo (n= 74). A total of 213 (59.2%) patients were primary induction failures, while 147 (40.8%) were in first or subsequent relapse. Graft source was peripheral blood in 92% of the patients. Patients transplanted from Haplo donors more frequently received marrow grafts (p< 0.01) and presented the combination female donor to male recipient (p< 0.01). The overall 2-year rates of overall survival (OS) and leukemia-free survival (LFS) were: 62.4% (95% CI 47.2–74.3) and 47.6% (95% CI 33.1–60.8) for MSD, 43% (95% CI 35.8–49.9), and 37.5% (95% CI 30.7–44.4) for MUD, and 25.9% (95% CI 15.8–37.2), and 26.5% (95% CI 16.3–37.8) for recipients of Haplo transplants. The 2-year cumulative incidence of relapse (RI) was slightly lower for Haplo recipients at 29.6% (95% CI 19–40.9), for MUD it was 30.2% (95% CI 23.9–36.7), and for MSD 34.9% (95% CI 22–48.2); counterbalanced by a higher incidence of non-relapse mortality (NRM) of 43.9% (95% CI 31.6–55.6) for Haplo recipients, 32.2% (95% CI 26–33.1) for MUD and 17.5% (95% CI 8.4–29.3) for MSD. Graft-versus-host disease (GVHD-free, relapse-free survival (GRFS) was 35.3% (95% CI 22.3–48.5) for MSD, 29.6% (95% CI 23.2–36.2) for MUD, and 19.2% (95% CI 10.7–29.6) for Haplo patients. In the multivariate model, compared to the referent group of MSD recipients, the risk of NRM was higher among patients transplanted from Haplo donors ([hazard ratio] HR 5.1, 95% CI 2.23–11.61, p< 0.001) and MUD (HR 3.21, 95% CI 1.48–0.6.94, p= 0.003). Furthermore, both Haplo and MUD were associated with inferior OS, (HR 3.6, 95% CI 1.98–0.6.56, p< 0.001, and HR 2.3, 95% CI 1.37–0.3.88, p= 0.002, respectively), and LFS (HR 2.24, 95% CI 1.31–0.3.84, p= 0.003, and HR 1.64, 95% CI 1.04–0.2.60, p= 0.034, respectively). Patients transplanted from Haplo donors were also associated with worse GFRS (HR 1.72, 95% CI 1.07–2.77, p:0.025) compared with MSD patients. Older adult AML patients with active disease transplanted from MSD experienced prolonged OS and LFS compared to 10/10 MUD and Haplo due to lower NRM. Prospective clinical trials are warranted.

We compared outcomes, of 1609 patients with secondary acute myeloid leukemia (sAML) undergoing allogeneic transplantation (HSCT) in first complete remission (CR1) from matched unrelated donors (MUD) from 2010 to 2021, receiving or not receiving anti-thymocyte globulin (ATG) (ATG-1308, no ATG-301). Median age was 60.9 (range, 18.5–77.8) and 61.1 (range, 21.8–75.7) years, (p= 0.3). Graft versus host disease (GVHD) prophylaxis was cyclosporin-A with methotrexate (41%) or mycophenolate mofetil (38.2%), without significant differences between groups. Day 28, engraftment (ANC > 0.5 × 109/L) was 92.3% vs 95.3% (p= 0.17), respectively. On multivariate analysis, ATG was associated with lower incidence of grade II-IV and grade III-IV acute GVHD (p= 0.002 and p= 0.015), total and extensive chronic GVHD (p= 0.008 and p< 0.0001), and relapse incidence (RI) (p= 0.039), while non-relapse mortality (NRM) did not differ (p= 0.51). Overall survival (OS), and GVHD-free, relapse-free survival (GRFS) were significantly higher in the ATG vs no ATG group, HR = 0.76 (95% CI 0.61–0.95, p= 0.014) and HR = 0.68 (95% CI 0.57–0.8, p< 0.0001), with a tendency for better leukemia-free survival (LFS), HR = 0.82 (95% CI 0.67–1, p= 0.051). The main causes of death were the original disease, infection, and GVHD. In conclusion, ATG reduces GVHD and improves LFS, OS, and GRFS in sAML patients without increasing the RI, despite sAML being a high-risk disease.

Allogeneic transplantation (allo-HCT) is a curative treatment in CLL whose efficacy including the most severe forms had led to the 2006 EBMT recommendations. The advent after 2014 of targeted therapies has revolutionized CLL management, allowing prolonged control to patients who have failed immunochemotherapy and/or have TP53 alterations. We analysed the pre COVID pandemic 2009–2019 EBMT registry. The yearly number of allo-HCT raised to 458 in 2011 yet dropped from 2013 onwards to an apparent plateau above 100. Within the 10 countries who were under the EMA for drug approval and performed 83.5% of those procedures, large initial differences were found but the annual number converged to 2–3 per 10 million inhabitants during the 3 most recent years suggesting that allo-HCT remains applied in selected patients. Long-term follow-up on targeted therapies shows that most patients relapse, some early, with risk factors and resistance mechanisms being described. The treatment of patients exposed to both BCL2 and BTK inhibitors and especially those with double refractory disease will become a challenge in which allo-HCT remains a solid option in competition with emerging therapies that have yet to demonstrate their long-term effectiveness.

Limited data is available on factors impacting the outcomes of second hematopoietic cell transplantation (HCT2) in patients with secondary acute myeloid leukemia (sAML). This study aimed to assess HCT2 outcome for sAML comparing reduced-intensity (RIC) to myeloablative (MAC) conditioning. Two hundred and fifteen patients were included: RIC (n= 134), MAC (n= 81). The median follow-up was 41.1 (95% CI: 26.7–69.3) and 28.5 (95% CI: 23.9–75.4) months, respectively. At two years, the relapse incidence (RI) was 58.3% versus 51.1% in RIC and MAC, respectively. The 2-year leukemia free survival (LFS) was 26.6% versus 26%, and the graft-versus-host disease (GVHD)-free, relapse-free survival (GRFS) was 16.4% versus 12.1%, while OS was 31.4% and 39.7%, for RIC and MAC respectively. MVA showed a significantly lower RI [hazard ratio (HR) = 0.46 (95% CI, 0.26–0.8, p= 0.006)] and improved LFS [HR = 0.62 (95% CI, 0.39–0.98, p= 0.042)] with MAC versus RIC. The choice of conditioning regimen did not impact non-relapse mortality [HR = 1.14 (95% CI, 0.52–2.5, p= 0.74)], overall survival (OS) [HR = 0.72 (95% CI, 0.44–1.17, p= 0.18)] or GRFS [HR = 0.89 (95% CI, 0.59–1.36, p= 0.6)]. In conclusion, MAC was associated with a lower RI and superior LFS. These results support the use of MAC for eligible patients with sAML who are being considered for HCT2.

•Recipients of allogeneic stem cell transplantation show high mortality from COVID-19.•Risk factors include older age, infection early after transplantation, and immunosuppression.•There was no significant decrease in mortality during the course of the pandemic.•The majority of patients developed mild COVID-19; main symptoms included fever, cough, dyspnea, fatigue, and gastrointestinal symptoms.

Comparative data of fludarabine, cytarabine and amsacrine (FLAMSA) chemotherapy followed by busulfan (Bu)-based reduced-intensity conditioning (RIC) (FLAMSA-Bu) versus RIC regimens are lacking in patients with active relapsed/refractory (R/R) acute myeloid leukemia (AML) at the time of allogeneic hematopoietic stem cell transplantation (alloSCT). Here, we retrospectively analyzed outcomes after FLAMSA-Bu versus fludarabine/busulfan (FluBu2) conditioning in this patient population. A total of 476 patients fulfilled the inclusion criteria, of whom 257 received FluBu2 and 219 FLAMSA-Bu. Median follow-up was 41 months. Two-year non-relapse mortality (21%), graft-versus-host disease-free, relapse-free survival (24%) and chronic graft-versus-host disease (GVHD) (29%) were not statistically different between cohorts. FLAMSA-Bu was associated with lower 2-year relapse incidence (RI) (38 vs 49% after FluBu2, p= 0.004), and increased leukemia-free survival (LFS) (42 vs 29%, p= 0.001), overall survival (47 vs 39%, p= 0.008) and grades II-IV acute GVHD (36 vs 20%, p= 0.001). In the multivariate analysis, FLAMSA-Bu remained associated with lower RI (HR 0.69, p= 0.042), increased LFS (HR 0.74, p= 0.048) and a higher risk of acute GVHD (HR 2.06, p= 0.005). Notwithstanding the limitations inherent in this analysis, our data indicate that FLAMSA-Bu constitutes a tolerable conditioning strategy, resulting in a long-term benefit in a subset of patients reaching alloSCT with active disease.

The association of Cyclosporine A (CsA) and mycophenolate mofetil (MMF) has increased in the setting of reduced intensity conditioning (RIC). Nevertheless, the use of CsA or CsA+MMF has not been reported in a large and uniform cohort. We analyzed 497 patients with acute myeloid leukemia in complete remission (CR) who underwent matched unrelated donor (MUD) hematopoietic stem cell transplantation (HSCT). All patients received a fludarabine busulfan RIC regimen and anti-thymocyte globulin (ATG) with either CsA alone or in combination with MMF. The cumulative incidence (CI) of grade II–IV acute GvHD was 27% (95% CI 21–33%) for CsA and 33% (95% CI 27–38%) for CsA+MMF (p= 0.25). The 2-year CI of chronic GvHD was 38% (95% CI 31–45%) and 33% (95% CI 28–39%) for the CsA and the CsA+MMF group, respectively (p= 0.26). On multivariate analysis, no statistically significant differences with respect to relapse incidence (RI), non-relapse mortality (NRM), leukemia-free survival (LFS), overall survival (OS), acute and chronic GvHD were found between the two groups, also when conducting a subgroup analysis in peripheral blood stem cells (PBSC) recipients. Our results support the importance of randomized trial to identify patients who could benefit from the addition of MMF in MUD HSCT.

Hyperbilirubinemia occurs frequently after allogeneic stem cell transplantation. Causes include primary liver damage and endothelial complications as major contributors. Here, we have investigated the impact of early bilirubinemia (EB) on posttransplant outcomes. Maximum total bilirubin levels (days 0–28) were categorized using maximally selected log rank statistics to identify a cut off for the endpoint non-relapse mortality (NRM) in a training cohort of 873 patients. EB above this cut off was correlated with NRM and overall survival (OS) and with pre- and posttransplant Angiopoietin-2, interleukin (IL)18, CXCL8 and suppressor of tumorigenicity-2 (ST2) serum levels, and the endothelial activation and stress index (EASIX). Clinical correlations were validated in a sample of 388 patients transplanted in an independent institution. The EB cut off was determined at 3.6 mg/dL (61.6 µM). EB predicted OS (HR 1.60, 95% CI 1.21–2.12, p< 0.001), and NRM (CSHR 2.14; 1.28–3.56, p= 0.004), also independent of typical endothelial complications such as veno-occlusive disease, refractory acute graft-versus-host disease, or transplant-associated microangiopathy. However, EB correlated with high Angiopoietin-2, EASIX-pre and EASIX-day 0, as well as increased levels of posttransplant CXCL8, IL18, and ST2. In summary, EB indicates a poor prognosis. The association of EB with endothelial biomarkers suggests an endothelial pathomechanism also for this posttransplant complication.

We aimed to evaluate the determinants of survival in myelofibrosis patients undergoing allogeneic hematopoietic cell transplantation (allo-HCT) and to describe factors predicting the main post-HCT complications. This retrospective study by the European Society for Blood and Marrow Transplantation included 2916 myelofibrosis patients who underwent first allo-HCT from an HLA-identical sibling or unrelated donor between 2000 and 2016. After a median follow-up of 4.7 years from transplant, projected median survival of the series was 5.3 years. Factors independently associated with increased mortality were age?=?60 years and Karnofsky Performance Status <90% at transplant, and occurrence of graft failure, grades III–IV acute graft-vs.-host disease (aGVHD), and disease progression/relapse during follow-up. The opposing effects of chronic graft-vs.-host disease (GVHD) on non-relapse mortality and relapse incidence resulted in a neutral influence on survival. Graft failure increased in unrelated donor recipients and decreased with myeloablative conditioning (MAC) and negative donor/recipient cytomegalovirus serostatus. Risk of grades III–IV aGVHD was higher with unrelated donors and decreased with MAC. Relapse incidence tended to be higher in patients with intermediate-2/high-risk DIPSS categories and to decrease in CALR-mutated patients. Acute and chronic GVHD reduced the subsequent risk of relapse. This information has potential implications for patient counseling and clinical decision-making.

Polycythaemia vera is a myeloproliferative neoplasm characterised by excessive proliferation of erythroid, myeloid, and megakaryocytic components in the bone marrow due to mutations in the Janus kinase 2 (JAK2)gene. Ruxolitinib, a JAK 1 and JAK 2 inhibitor, showed superiority over best available therapy in a phase 2 study in patients with polycythaemia vera who were resistant to or intolerant of hydroxyurea. We aimed to compare the long-term safety and efficacy of ruxolitinib with best available therapy in patients with polycythaemia vera who were resistant to or intolerant of hydroxyurea.

Introduction: Elotuzumab, a monoclonal antibody targeting SLAM family member 7 protein (SLAMF7) on multiple myeloma (MM) cells, has shown promise in relapsed/refractory MM when combined with immunomodulatory agents. However, its effectiveness in newly diagnosed patients did not show improved progression-free survival (PFS) nor overall survival. In a previous study we demonstrated that elotuzumab specifically depleted high SLAMF7 expressing regulatory CD8 +T cells by macrophage induced antibody dependent phagocytosis. This study aimed to identify immunological predictive factors for elotuzumab efficacy, enabling improved risk stratification and personalized treatment decisions based on the detection and quantification of SLAMF7-positive T cell subsets.

Acute myeloid leukemia with t(8;21)(q22;q22) is characterized by considerable clinical and biological heterogeneity leading to relapse in up to 40% of patients. We sequenced coding regions or hotspot areas of 66 recurrently mutated genes in a cohort of 331 t(8;21) patients. At least 1 mutation, in addition to t(8;21), was identified in 95%, with a mean of 2.2 driver mutations per patient. Recurrent mutations occurred in genes related to RAS/RTK signaling (63.4%), epigenetic regulators (45%), cohesin complex (13.6%), MYC signaling (10.3%), and the spliceosome (7.9%). Our study identified mutations in previously unappreciated genes: GIGYF2, DHX15, and G2E3. Based on high mutant levels, pairwise precedence, and stability at relapse, epigenetic regulator mutations were likely to occur before signaling mutations. In 34% of RAS/RTKmutated patients, we identified multiple mutations in the same pathway. Deep sequencing (~42?000×) of 126 mutations in 62 complete remission samples from 56 patients identified 16 persisting mutations in 12 patients, of whom 5 lacked RUNX1-RUNX1T1 in quantitative polymerase chain reaction analysis. KIThigh mutations defined by a mutant level =25% were associated with inferior relapse-free survival (hazard ratio, 1.96; 95% confidence interval, 1.22-3.15; P = .005). Together with age and white blood cell counts, JAK2, FLT3-internal tandem duplicationhigh, and KIThigh mutations were identified as significant prognostic factors for overall survival in multivariate analysis. Whole-exome sequencing was performed on 19 paired diagnosis, remission, and relapse trios. Exome-wide analysis showed an average of 16 mutations with signs of substantial clonal evolution. Based on the resemblance of diagnosis and relapse pairs, genetically stable (n = 13) and unstable (n = 6) subgroups could be identified.

Acute myeloid leukemia with t(8;21)(q22;q22) is characterized by considerable clinical and biological heterogeneity leading to relapse in up to 40% of patients. We sequenced coding regions or hotspot areas of 66 recurrently mutated genes in a cohort of 331 t(8;21) patients. At least 1 mutation, in addition to t(8;21), was identified in 95%, with a mean of 2.2 driver mutations per patient. Recurrent mutations occurred in genes related to RAS/RTK signaling (63.4%), epigenetic regulators (45%), cohesin complex (13.6%), MYC signaling (10.3%), and the spliceosome (7.9%). Our study identified mutations in previously unappreciated genes: GIGYF2, DHX15, and G2E3. Based on high mutant levels, pairwise precedence, and stability at relapse, epigenetic regulator mutations were likely to occur before signaling mutations. In 34% of RAS/RTKmutatedpatients, we identified multiple mutations in the same pathway. Deep sequencing (∼42 000×) of 126 mutations in 62 complete remission samples from 56 patients identified 16 persisting mutations in 12 patients, of whom 5 lacked RUNX1-RUNX1T1in quantitative polymerase chain reaction analysis. KIThighmutations defined by a mutant level ≥25% were associated with inferior relapse-free survival (hazard ratio, 1.96; 95% confidence interval, 1.22-3.15; P= .005). Together with age and white blood cell counts, JAK2, FLT3-internal tandem duplicationhigh, and KIThighmutations were identified as significant prognostic factors for overall survival in multivariate analysis. Whole-exome sequencing was performed on 19 paired diagnosis, remission, and relapse trios. Exome-wide analysis showed an average of 16 mutations with signs of substantial clonal evolution. Based on the resemblance of diagnosis and relapse pairs, genetically stable (n = 13) and unstable (n = 6) subgroups could be identified.

Pulmonale Komplikationen treten bei hämatologischen Patienten häufig auf. In einer Übersichtsarbeit wird das Ergebnis einer Diskussion zusammengefasst, die während eines Expertentreffens zum Thema Lungeninfiltrate stattfand. Die häufigsten Ursachen von Lungeninfiltraten bei hämatologischen Patienten sind bakterielle Infektionen, aber auch Virusinfektionen verursachen, zum Teil mit relevanter saisonaler Schwankung, einen wichtigen Anteil pulmonaler Infiltrate. Für beide Erregergruppen stellt die mikrobiologische Untersuchung von Materialien des Respirationstrakts (möglichst bronchoalveoläre Lavage, BAL) die wichtigste Diagnostik dar. Insbesondere bei länger anhaltender (> 7 Tage) Neutropenie steigt die Wahrscheinlichkeit, dass Infiltrate durch Pilzinfektionen bedingt sind. Nichtinfektiöse Ursachen, z. B. durch Medikamente bedingte Infiltrate, sind differentialdiagnostisch grundsätzlich zu berücksichtigen, dürfen jedoch eine schnelle Diagnostik und adäquate antimikrobielle Therapie nicht verzögern. Pulmonary complications are frequent in haematologic patients. This review article summarizes the outcome of a discussion that took place during an expert meeting on the subject of pulmonary infiltrates. The most common causes of pulmonary infiltrates in haematologic patients are bacterial infections. Viral infections are subject to relevant seasonal variations, but they may also cause an important proportion of pulmonary infiltrates. Microbiological examination of respiratory tract material (if possible, bronchoalveolar lavage, BAL) is the most important diagnostic procedure. Particularly in the case of prolonged (> 7 days) neutropenia, the likelihood of infiltrates being caused by fungal infections increases. For a differential diagnosis, however, also non-infectious causes, e.g. drug-induced infiltrates, have to be taken into consideration. The diagnostic workup, however, should not delay a timely start of an adequate antimicrobial therapy.

We investigated subclonal cytogenetic aberrations (CA) detected by interphase fluorescence in situ hybridization (iFISH) in patients with newly diagnosed multiple myeloma (MM) enrolled in the Haemato Oncology Foundation for Adults in the Netherlands (HOVON)–65/German-Speaking MM Group (GMMG)–HD4 phase 3 trial. Patients were either treated with 3 cycles of vincristine, Adriamycin, and dexamethasone or bortezomib, Adriamycin, and dexamethasone and then thalidomide or bortezomib maintenance after tandem autologous transplantation. Subclones were defined either by presence of different copy numbers of the same chromosome loci and/or CA present in at least 30% less and maximally 2/3 of cells compared with the main clone CA. Patients with subclones harbored more frequently high risk (31.0%) or hyperdiploid main clone aberrations (24.8%) than patients with t(11;14) in the main clone (10.1%). Gains and deletions of c-MYC were the only CA that occurred more frequently as subclone (8.1%/20.5%) than main clone (6.2%/3.9%, respectively). Treatment with bortezomib completely overcame the negative prognosis of high-risk CA in patients without subclones, but not in patients with additional subclonal CA. High-risk patients treated without bortezomib showed dismal outcome whether subclones were present or not. Cytogenetic heterogeneity defined by subclonal CA is of major prognostic significance in newly diagnosed MM patients treated with bortezomib within the HOVON-65/GMMG-HD4 trial.

•In chronic myeloid leukemia (CML) patients undergoing allo-HCT from an unrelated donor (UD), post-transplant cyclophosphamide (PTCy) or a mainly CNI (calcineurin inhibitor)-based GvHD prophylaxis associate with similar GRFS, OS, NRM, PFS and RI.•PTCy UD and PTCy mismatched related donor are feasible allo-HCT platforms in CML patients.•Disease status, Karnofsky performance status and patient's age remain strong prognostic factors for survival in allo-HCT for CML, highlighting the important of performing allo-HCT when indicated.

Acute myeloid leukemia (AML) with an FLT3 internal tandem duplication (FLT3-ITD) mutation is an aggressive hematologic malignancy with a grave prognosis. To identify the mutational spectrum associated with relapse, whole-exome sequencing was performed on 13 matched diagnosis, relapse, and remission trios followed by targeted sequencing of 299 genes in 67 FLT3-ITD patients. The FLT3-ITD genome has an average of 13 mutations per sample, similar to other AML subtypes, which is a low mutation rate compared with that in solid tumors. Recurrent mutations occur in genes related to DNA methylation, chromatin, histone methylation, myeloid transcription factors, signaling, adhesion, cohesin complex, and the spliceosome. Their pattern of mutual exclusivity and cooperation among mutated genes suggests that these genes have a strong biological relationship. In addition, we identified mutations in previously unappreciated genes such as MLL3, NSD1, FAT1, FAT4, and IDH3B. Mutations in 9 genes were observed in the relapse-specific phase. DNMT3A mutations are the most stable mutations, and this DNMT3A-transformed clone can be present even in morphologic complete remissions. Of note, all AML matched trio samples shared at least 1 genomic alteration at diagnosis and relapse, suggesting common ancestral clones. Two types of clonal evolution occur at relapse: either the founder clone recurs or a subclone of the founder clone escapes from induction chemotherapy and expands at relapse by acquiring new mutations. Relapse-specific mutations displayed an increase in transversions. Functional assays demonstrated that both MLL3 and FAT1 exert tumor-suppressor activity in the FLT3-ITD subtype. An inhibitor of XPO1 synergized with standard AML induction chemotherapy to inhibit FLT3-ITD growth. This study clearly shows that FLT3-ITD AML requires additional driver genetic alterations in addition to FLT3-ITD alone.

Acute myeloid leukemia (AML) with an FLT3internal tandem duplication (FLT3-ITD) mutation is an aggressive hematologic malignancy with a grave prognosis. To identify the mutational spectrum associated with relapse, whole-exome sequencing was performed on 13 matched diagnosis, relapse, and remission trios followed by targeted sequencing of 299 genes in 67 FLT3-ITD patients. The FLT3-ITD genome has an average of 13 mutations per sample, similar to other AML subtypes, which is a low mutation rate compared with that in solid tumors. Recurrent mutations occur in genes related to DNA methylation, chromatin, histone methylation, myeloid transcription factors, signaling, adhesion, cohesin complex, and the spliceosome. Their pattern of mutual exclusivity and cooperation among mutated genes suggests that these genes have a strong biological relationship. In addition, we identified mutations in previously unappreciated genes such as MLL3, NSD1, FAT1, FAT4, and IDH3B. Mutations in 9 genes were observed in the relapse-specific phase. DNMT3Amutations are the most stable mutations, and this DNMT3A-transformed clone can be present even in morphologic complete remissions. Of note, all AML matched trio samples shared at least 1 genomic alteration at diagnosis and relapse, suggesting common ancestral clones. Two types of clonal evolution occur at relapse: either the founder clone recurs or a subclone of the founder clone escapes from induction chemotherapy and expands at relapse by acquiring new mutations. Relapse-specific mutations displayed an increase in transversions. Functional assays demonstrated that both MLL3and FAT1exert tumor-suppressor activity in the FLT3-ITD subtype. An inhibitor of XPO1synergized with standard AML induction chemotherapy to inhibit FLT3-ITD growth. This study clearly shows that FLT3-ITD AML requires additional driver genetic alterations in addition to FLT3-ITD alone.

Mesenchymal stromal cells (MSCs) are an essential cell type of the hematopoietic microenvironment. Concerns have been raised about the possibility that MSCs undergo malignant transformation. Several studies, including one from our own group, have shown the presence of cytogenetic abnormalities in MSCs from leukemia patients. The aim of the present study was to compare genetic aberrations in hematopoietic cells (HCs) and MSCs of myelodysplastic syndrome (MDS) and acute myeloid leukemia (AML) patients. Cytogenetic aberrations were detected in HCs from 25 of 51 AML patients (49%) and 16 of 43 MDS patients (37%). Mutations of the FLT3 and NPM1 genes were detected in leukemic blasts in 12 (23%) and 8 (16%) AML patients, respectively. Chromosomal aberrations in MSCs were detected in 15 of 94 MDS/AML patients (16%). No chromosomal abnormalities were identified in MSCs of 36 healthy subjects. We demonstrate herein that MSCs have distinct genetic abnormalities compared with leukemic blasts. We also analyzed the main characteristics of patients with MSCs carrying chromosomal aberrations. In view of these data, the genetic alterations in MSCs may constitute a particular mechanism of leukemogenesis.

This study investigated the immunogenicity of Wilms tumor gene product 1 (WT1)–peptide vaccination in WT1-expressing acute myeloid leukemia (AML) and myelodysplastic syndrome (MDS) patients without curative treatment option. Vaccination consisted of granulocyte-macrophage colony-stimulating factor subcutaneously days 1 to 4, and WT1.126-134 peptide and 1 mg keyhole limpet hemocyanin on day 3. The initial 9 patients received 4 vaccinations biweekly, then monthly, and the subsequent 10 patients received continual biweekly vaccination. Seventeen AML patients and 2 refractory anemia with excess blasts patients received a median of 11 vaccinations. Treatment was well tolerated. Objective responses in AML patients were 10 stable diseases (SDs) including 4 SDs with more than 50% blast reduction and 2 with hematologic improvement. An additional 4 patients had clinical benefit after initial progression, including 1 complete remission and 3 SDs. WT1 mRNA levels decreased at least 3-fold from baseline in 35% of patients. In 8 of 18 patients, WT1-tetramer+ T cells increased in blood and in 8 of 17 patients in bone marrow, with a median frequency in bone marrow of 0.18% at baseline and 0.41% in week 18. This WT1 vaccination study provides immunologic, molecular, and preliminary evidence of potential clinical efficacy in AML patients, warranting further investigations.

This study investigated the immunogenicity of Wilms tumor gene product 1 (WT1)–peptide vaccination in WT1-expressing acute myeloid leukemia (AML) and myelodysplastic syndrome (MDS) patients without curative treatment option. Vaccination consisted of granulocyte-macrophage colony-stimulating factor subcutaneously days 1 to 4, and WT1.126-134 peptide and 1 mg keyhole limpet hemocyanin on day 3. The initial 9 patients received 4 vaccinations biweekly, then monthly, and the subsequent 10 patients received continual biweekly vaccination. Seventeen AML patients and 2 refractory anemia with excess blasts patients received a median of 11 vaccinations. Treatment was well tolerated. Objective responses in AML patients were 10 stable diseases (SDs) including 4 SDs with more than 50% blast reduction and 2 with hematologic improvement. An additional 4 patients had clinical benefit after initial progression, including 1 complete remission and 3 SDs. WT1 mRNA levels decreased at least 3-fold from baseline in 35% of patients. In 8 of 18 patients, WT1-tetramer+T cells increased in blood and in 8 of 17 patients in bone marrow, with a median frequency in bone marrow of 0.18% at baseline and 0.41% in week 18. This WT1 vaccination study provides immunologic, molecular, and preliminary evidence of potential clinical efficacy in AML patients, warranting further investigations.