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The treatment of low-tumour burden follicular lymphoma (LTBFL) remains a challenge. Rituximab-based strategies may be improved by adding chemotherapy. This Lymphoma Study Association multicentre phase II study assessed rituximab and bendamustine in 63 patients with untreated LTBFL who were aged over 60 years old and had a follicular lymphoma International Prognostic Index (FLIPI) score ≥2. Induction comprised 4 weekly cycles of rituximab 375 mg/m 2 intravenously combined with 2 cycles of bendamustine 90 mg/m 2 days 1-2 with a 28-day interval, followed by twelve cycles of 375 mg/m 2 rituximab maintenance therapy every 8 weeks. The primary endpoint was complete response (CR)/unconfirmed CR (CRu), at 12 weeks. Median age was 67·4 years and median FLIPI was 3. Ultimately, 18 patients (29%) had high tumour burden according to Groupe d'Etude des Lymphomes Folliculaires criteria. The 12-week CR/CRu rate was 54·0% and the overall response rate was 93·7%. Surprisingly, 3 patients died during maintenance (2 sepsis, 1 neoplasm). Progression-free survival was 85·4% at 24 months. In LTBFL patients with FLIPI ≥2, two cycles of rituximab and bendamustine result in a CR rate of 54·0%. However, the treatment-related deaths observed do not allow this regimen to be recommended for LTBFL patients aged over 60 years. EudraCT: 2010-020757-14; ClinicalTrials.gov: NCT01313611., (© 2018 British Society for Haematology and John Wiley & Sons Ltd.)

BCL2 mutations have been suggested to confer an adverse prognosis to follicular lymphoma (FL) patients, but their prognostic value has not been assessed in patients treated with a rituximab-containing regimen. Here we evaluated the prognostic value of BCL2 mutations in a large prospective cohort of 252 patients with FL treated with immunochemotherapy in the PRIMA randomized trial. Using a DNA-targeted sequencing approach, we detected amino acid altering mutations in 135 patients (54%) and showed that these mutations were probably mediated by the over-activation of AICDA (activation-induced cytidine deaminase) in the context of the t(14;18) translocation. The BCL2 variants identified in PRIMA patients affected the BH1, BH2, and BH3 functional motifs at a lower frequency than the N-terminus and flexible loop domain, with mostly conservative aminoacid changes. With a median follow-up of 6.7 years, we did not observe any impact of BCL2 mutations either on overall survival or progression-free survival., (© 2017 Wiley Periodicals, Inc.)

The myelodysplastic syndromes (MDSs) are a heterogeneous group of clonal haematological diseases characterized by ineffective haematopoiesis and predisposition to acute myeloid leukaemia (AML). The pathophysiology of MDSs remains unclear. A definition of the molecular biology of MDSs may lead to a better classification, new prognosis indicators and new treatments. We studied a series of 40 MDS/AML samples by high-density array-comparative genome hybridization (aCGH). The genome of MDSs displayed a few alterations that can point to candidate genes, which potentially regulate histone modifications and WNT pathways (e.g. ASXL1, ASXL2, UTX, CXXC4, CXXC5, TET2, TET3). To validate some of these candidates we studied the sequence of ASXL1. We found mutations in the ASXL1 gene in four out of 35 MDS patients (11%). To extend these results we searched for mutations of ASXL1 in a series of chronic myelomonocytic leukaemias, a disease classified as MDS/Myeloproliferative disorder, and found mutations in 17 out of 39 patients (43%). These results show that ASXL1 might play the role of a tumour suppressor in myeloid malignancies.

The ubiquitous herpesvirus Epstein-Barr virus (EBV) is linked to the development of several malignancies, including nasopharyngeal carcinoma (UCNT) and Hodgkin lymphoma (HL). Despite the well-known oncogenic properties of the EBV latent membrane protein 1 (LMP-1), the different oncogenic pathways involved in the pathogenesis of each disease remain unclear. This study reported, for the first time, the case of a patient with sequential development of UCNT and HL. Polymerase chain reaction was used to determine the LMP-1 gene sequence and demonstrate that the two tumours contained different clonal viral genomes, suggesting a central and specific role of EBV infection.

The influence of bone marrow biopsy (BMB) histology on prognosis and management of follicular lymphomas (FL) remains controversial. A total of 390 patients with grade 1 or 2 FL were prospectively included in the multicentric Groupe d'Etude des Lymphomes Folliculaires trial and their BMB reviewed in order (i) to quantify the ratio of lymphomatous foci (LFo) area to that of BMB size (LFo/BMB), (ii) to determine the BMB patterns for a practical grading of marrow infiltration, (iii) to assess the intra- and inter-observer reproducibility of this grading and (iv) to analyse this grading on event-free (EFS) and overall survival (OS), using univariate and multivariate analyses. A total of 267 patients (68%) had BMB involvement, with inter- and intra-observer reproducibility for classifying the patterns of involvement of 91 and 96%, respectively. Uni- and multivariate analyses demonstrated the adverse influence of (i) a ratio of LFo/BMB > or = 0.1, i.e. three or four nodules/medullary space or > or = 1 nodule + foci of diffuse involvement on EFS (P = 0.03) and (ii) two different histological patterns in the same BMB on EFS (P = 0.004) and OS (P = 0.001). This latter finding was only significant in patients with a high tumour burden and remained significant in multivariate analysis. These results indicate that BMB histology can predict survival of FL patients with a high tumour burden, and may help in defining their treatment., (Copyright 2004 Blackwell Publishing Ltd)

True histiocytic lymphoma (THL) is a very rare type of non-Hodgkin's lymphoma (NHL) in which neoplastic cells exhibit markers of histiocytic differentiation. Some cases of THL have been reported in patients with previous acute lymphoblastic leukaemia (ALL), especially in children and young adults, in whom the acute leukaemia was of T-cell origin. The relationship between the initial lymphoid tumour and the secondary THL remains unclear, as a common monoclonal origin shared by both neoplasms has never been definitively demonstrated. We report a patient with B-ALL who developed a nodal and extranodal tumour with histological and immunohistochemical features of THL 4 years after the initial diagnosis. Genotypic study showed that both neoplasms contained the same immunoglobulin heavy gene rearrangement, which has not been reported previously.

We have previously shown that malignant B cells from non-Hodgkin's lymphomas (NHL) are resistant to Fas-mediated apoptosis. To determine the mechanisms underlying this resistance, we analysed by Western blotting the expression of several apoptotic regulators, caspase 3, caspase 8, FADD and poly(ADP-ribose) polymerase (PARP) in fresh lymphoma cells, isolated from 16 B-NHL biopsy samples of different histological subtypes, and displaying variable levels of Fas expression. The profiles of expression of these apoptotic regulators were monitored in cell lysates at different times following Fas with or without CD40 stimulation. Expression of FADD and of the uncleaved forms of PARP, caspase 3 and caspase 8 were detected in all untreated NHL samples. Low levels of PARP cleavage were noted in three untreated samples. Fas stimulation alone induced neither significant apoptosis nor significant changes in the expression profiles of FADD, caspases 3 and 8 and PARP in the 16 samples, except for variations in FADD and caspase 8 expression levels in a minority of samples. Fas/CD40 co-stimulation induced apoptosis and cleavage of caspase 3, caspase 8 and PARP in the five NHLs tested; expression of FADD was not modified. Our results showed (1) that induction of apoptosis in B-NHLs by Fas/CD40 co-stimulation used the same caspase executioner machinery as the normal Fas pathway, and (2) that NHL cells which resisted Fas-mediated apoptosis displayed no defect in either expression or functionality of caspases 3 and 8, nor in FADD expression. The dysfunction underlying NHL resistance to apoptosis must therefore lie upstream of caspase 8, or could alternatively be influenced by anti-apoptotic regulators of the Bcl-2 family.

Bcl-x is a member of the bcl-2 family of proteins which are characterized by their ability to modulate apoptosis. Alternative splicing results in two distinct bcl-x mRNAs encoding a long isoform, bcl-xL, which acts as a bcl-2 agonist; and a short isoform, bcl-xS, which inhibits bcl-2 effects. The aim of the study was to determine whether bcl-x is expressed in lymphoma tissues and to characterize the respective production of bcl-xs and bcl-xL. We investigated the expression of bcl-x mRNA in a series of 50 non-Hodgkin's lymphomas (NHL) and Hodgkin's disease (HD) cases using a RT-PCR method in order to amplify both transcripts simultaneously, and to estimate their relative abundance. The rearrangements of the bcl-2 gene were analysed by RT-PCR expression of the hybrid bcl-2-lgH mRNA. In addition, 20 PCR-positive NHL cases and three HD cases were analysed by immunohistochemistry using bcl-x polyclonal antisera. RT-PCR showed bcl-x expression in 43/45 NHLs and 5/5 HD cases. The bcl-xL transcript was predominant in all positive cases and was associated with variable amounts of bcl-xS. There was no significant correlation between the profile of bcl-xL/bcl-xS expression and the histological and immunological subtyping. Bcl-x immunodetection was positive in the neoplastic cell component in all analysed cases, but the degree of staining was highly variable between cases. Expression of the hybrid bcl-2-IgH gene was detected by RT-PCR in five cases of follicular NHL and in one case of HD, but this group of tumours did not display a particular profile of bcl-xL/bcl-xS expression. We conclude that bcl-x is commonly expressed by malignant cells in various types of malignant lymphomas, with a predominance of the bcl-xL transcript. Since the corresponding bcl-xL isoform can block the cell death machinery and potentialize bcl-2 effects, it may be involved in some pathways of lymphomagenesis.