BCL3 rearrangements in B-cell lymphoid neoplasms occur in two breakpoint clusters associated with different diseases.

The t(14;19)(q32;q13) often juxtaposes BCL3 with immunoglobulin heavy chain (IGH) resulting in overexpression of the gene. In contrast to other oncogenic translocations, BCL3 rearrangement (BCL3-R) has been associated with a broad spectrum of lymphoid neoplasms. Here we report an integrative whole-genome sequence, transcriptomic, and DNA methylation analysis of 13 lymphoid neoplasms with BCL3-R. The resolution of the breakpoints at single base-pair revealed that they occur in two clusters at 5' (n=9) and 3' (n=4) regions of BCL3 associated with two different biological and clinical entities. Both breakpoints were mediated by aberrant class switch recombination of the IGH locus. However, the 5' breakpoints (upstream) juxtaposed BCL3 next to an IGH enhancer leading to overexpression of the gene whereas the 3' breakpoints (downstream) positioned BCL3 outside the influence of the IGH and were not associated with its expression. Upstream BCL3-R tumors had unmutated IGHV, trisomy 12, and mutated genes frequently seen in chronic lymphocytic leukemia (CLL) but had an atypical CLL morphology, immunophenotype, DNA methylome, and expression profile that differ from conventional CLL. In contrast, downstream BCL3-R neoplasms were atypical splenic or nodal marginal zone lymphomas (MZL) with mutated IGHV, complex karyotypes and mutated genes typical of MZL. Two of the latter four tumors transformed to a large B-cell lymphoma. We designed a novel fluorescence in situ hybridization assay that recognizes the two different breakpoints and validated these findings in 17 independent tumors. Overall, upstream or downstream breakpoints of BCL3-R are mainly associated with two subtypes of lymphoid neoplasms with different (epi)genomic, expression, and clinicopathological features resembling atypical CLL and MZL, respectively.

Increasing therapy-related myeloid neoplasms in multiple myeloma.

BACKGROUND: Despite the longer survival achieved in multiple myeloma (MM) patients due to new therapy strategies, a concern is emerging regarding an increased risk of secondary primary malignancies (SPMs) and how to characterize those patients at risk. We performed a retrospective study covering a 28-year follow-up period (1991-2018) in a tertiary single institution. MATERIAL AND METHODS: Data of 403 MM patients were recorded and compared with the epidemiologic register of the population area covered by our centre, calculating the standardize incidence ratio (SIR) for the different types of SPMs diagnosed in the MM cohort. Fine and Gray regression models were used to identify risk factors for SPMs. RESULTS: Out of the 403 MM patients, 23 (5.7%) developed SPMs: 13 therapy-related myeloid (TRM) malignancies (10 of them (77%) myelodysplastic syndrome (MDS), 1 acute lymphoid leukaemia and 9 solid neoplasms. In the MM cohort, the relative risk of MDS was significantly higher than in the general population. Survival of patients with TRM malignancies was poor with a median of 4 months from the diagnosis, and most of them showed complex karyotype. Within the MM subset, multivariable analysis showed a higher risk of TRM malignancies in patients that previously received prolonged treatment with lenalidomide (>18 months). CONCLUSIONS: Though the improvement in MM outcome during the last decades is an unprecedented achievement, it has been accompanied by the rise in TRM malignancies with complex cytogenetic profile and poor prognosis that are in the need of an improved biologic and therapeutic approach.

VHrare study: Prevalence, clinical features and management of severe rare bleeding disorders in a large cohort.

INTRODUCTION: Rare bleeding disorders (RBD) constitute 5% of total hereditary bleeding disorders, although the number could be higher, due to the presence of undiagnosed asymptomatic patients. The objective of this study was to analyze the prevalence and characteristics of patients with severe RBDs in our area. MATERIAL AND METHODS: We analyzed the patients with RBD followed at a tertiary-level hospital between January 2014 and December 2021. RESULTS: A total of 101 patients were analyzed, with a median age at diagnosis of 27.67 years (range 0-89), of which 52.47% were male. The most frequent RBD in our population was FVII deficiency. Regarding the diagnostic reason, the most frequent cause was a preoperative test and only 14.8% reported bleeding symptoms at the time of diagnosis. A genetic study was carried out in 63.36% of patients and the most frequent mutation type found was finding a missense mutation. CONCLUSIONS: The distribution of RBDs in our centre is similar to the one reported in the literature. The majority of RBDs were diagnosed from a preoperative test and this allowed preventive treatment prior to invasive procedures to avoid bleeding complications. 83% of patients did not have a pathological bleeding phenotype according to ISTH-BAT.

Impact of risk scores in outcome of patients with myeloid neoplasms after allogeneic stem cell transplant.

BACKGROUND: The main causes of failure of allogeneic hematopoietic stem cell transplantation (allo-transplant) in patients with acute myeloid leukemia (AML) and myelodysplastic syndromes (MDS) are relapse and transplant-related mortality. Different scores have been designed to predict the prognosis of these patients. The objective of this study was to assess which score or combination has better outcome predictive capacity. METHODS: Retrospective analysis of patients with AML and MDS who received a first peripheral blood allo-transplant in a single center, between December 2001 and October 2019. Hematopoietic Cell Transplantation Comorbidity Index (HCT-CI), European Group for Blood and Marrow Transplantation (EBMT) and Disease Risk Index (DRI) scores were calculated. For each score and for the HCT-CI/DRI and HCT-CI/EBMT combinations, overall survival (OS), cumulative incidence of relapse (CIR), non-relapse-related mortality (NRM), and graft versus host disease-free relapse-free survival (GRFS) were analyzed. RESULTS: 175 patients were evaluated. With a median (range) follow-up of 3.96 (0.32-17.22) years, the 5-year probabilities (95% CI) of OS, CIR, NRM, and GRFS were 36% (28%-44%), 28% (21%-35%), 38% (30%-46%) and 24% (17%-31%), respectively. For OS, only the DRI score selected two groups with statistically significant differences (DRI 0-1: 41% vs. DRI ≥2: 24%; p=0.011). The combination of DRI 0-1 and HCT-CI 0-2 showed OS probabilities of 45% vs. 26% for those with DRI 0-1 and HCT-CI ≥3; p=0.041. CONCLUSIONS: In patients with AML and MDS submitted to allo-transplant, the combination of HCT-CI and DRI scores provided the best stratification for OS.