EBV-positive diffuse large B-cell lymphoma of the elderly

Epstein-Barr virus (EBV) positive diffuse large B-cell lymphoma (DLBCL) of the elderly, initially described in 2003, is a provisional entity in the 2008World Health Organization classification system and is defined as an EBV-positive monoclonal large B-cell proliferation that occurs in patients >50 years of age and in whom there is no known immunodeficiency or history of lymphoma. These tumors are more common in Asia but also occur in North America and Europe at a low frequency. These neoplasms exhibit a morphologic continuum, from polymorphous to monomorphous, but morphologic features do not correlate with prognosis as all patients have a clinically aggressive course. Most EBV-positive DLBCL of the elderly patients have an activated B-cell immunophenotype and are characterized by prominent nuclear factor-kB activation. Cytogenetic complexity is usually low. In this review, we comprehensively delineate the data emerging from analyses of EBV latency program, microRNA-mediated EBV viral oncogenesis, functional genomics of EBV and its biology, and differential diagnosis challenge for EBV-positive DLBCL of the elderly. It is hoped that the improved understanding of these tumors will lead to the development of novel therapeutic approaches, enhance the effectiveness of clinical trials, and improve prognosis

High p53 protein expression in therapy-related myeloid neoplasms is associated with adverse karyotype and poor outcome

Molecular tumour pathology - and tumour genetic

Calibration of the CREAM calorimeter with beam test data

International audienc

Calibration of the CREAM calorimeter with beam test data

International audienc

An Automated and Robust Tumours Detection and Segmentation Framework for Whole-Body PET-CT Studies

A dual-modality positron emission tomography – computed tomography (PET-CT) is one of widely used medical imaging system. It combines functional (from PET) with anatomical (from CT) information, in a co-aligned space, provides advantages on diagnosing with several types of cancers. The most unique benefit of PET is to noninvasively visualise metabolic information such as glucose metabolism, through administrating radioactive tracer into the human body and quantitatively assess treatment response by analysing tumours metabolism. PET response criterion in solid tumour (PERCIST) is a widely accepted approach of assessing metabolic response of malignant tumours. It suggests placing volume of interest (VOI) reference on the liver structure (or the descending aorta structure if the liver is diseased, e.g. liver cancer) of the PET image to measure average of pixel variations. VOI references are then used to derive a PERCIST-based thresholding value, where the structures’ metabolism comprising of higher than the threshold will be considered as tumours. However, the delineation of VOI reference on the low resolution and poor signal-to-noise ratio (SNR) PET image is a difficult, time consuming and subjective task; in particular, for the small descending aorta structure. In addition, the global threshold does not provide accurate delineation of the tumour structure on PET. In this study, we propose a fully automatic tumours detection and segmentation framework for whole-body PET-CT studies based on PERCIST. We used multi-atlas based approach to segment PERCIST recommended VOI reference and to detect tumours. Then we used cellular automata with anisotropic diffusion filter (CA-ADF) based algorithm for accurate tumour segmentation on PET. In our evaluation, both clinical and simulation results presented that our proposed framework was able to detect and segment all the tumours with high accuracy, which demonstrated the reliability and robustnes

Evaluation of NF-kappaB subunit expression and signaling pathway activation demonstrates that p52 expression confers better outcome in germinal center B-cell-like diffuse large B-cell lymphoma in association with CD30 and BCL2 functions

Contains fulltext : 155215.pdf (publisher's version ) (Closed access)Nuclear factor-kappaB (NF-kappaB) is a transcription factor with a well-described oncogenic role. Study for each of five NF-kappaB pathway subunits was only reported on small cohorts in diffuse large B-cell lymphoma (DLBCL). In this large cohort (n=533) of patients with de novo DLBCL, we evaluated the protein expression frequency, gene expression signature, and clinical implication for each of these five NF-kappaB subunits. Expression of p50, p52, p65, RELB, and c-Rel was 34%, 12%, 20%, 14%, and 23%, whereas p50/p65, p50/c-Rel, and p52/RELB expression was 11%, 11%, and 3%, respectively. NF-kappaB subunits were expressed in both germinal center B-cell-like (GCB) and activated B-cell-like (ABC) DLBCL, but p50 and p50/c-Rel were associated with ABC-DLBCL. p52, RELB, and p52/RELB expressions were associated with CD30 expression. p52 expression was negatively associated with BCL2 (B-cell lymphoma 2) expression and BCL2 rearrangement. Although p52 expression was associated with better progression-free survival (PFS) (P=0.0170), singular expression of the remaining NF-kappaB subunits alone did not show significant prognostic impact in the overall DLBCL cohort. Expression of p52/RELB was associated with better overall survival (OS) and PFS (P=0.0307 and P=0.0247). When cases were stratified into GCB- and ABC-DLBCL, p52 or p52/RELB dimer expression status was associated with better OS and PFS (P=0.0134 and P=0.0124) only within the GCB subtype. However, multivariate analysis did not show p52 expression to be an independent prognostic factor. Beneficial effect of p52 in GCB-DLBC appears to be its positive correlation with CD30 and negative correlation with BCL2 expression. Gene expression profiling (GEP) showed that p52(+) GCB-DLBCL was distinct from p52(-) GCB-DLBCL. Collectively, our data suggest that DLBCL patients with p52 expression might not benefit from therapy targeting the NF-kappaB pathway

Prognostic impact of c-Rel nuclear expression and REL amplification and crosstalk between c-Rel and the p53 pathway in diffuse large B-cell lymphoma

Contains fulltext : 153743.pdf (publisher's version ) (Closed access)Dysregulated NF-kappaB signaling is critical for lymphomagenesis. The regulation, function, and clinical relevance of c-Rel/NF-kappaB activation in diffuse large B-cell lymphoma (DLBCL) have not been well studied. In this study we analyzed the prognostic significance and gene-expression signature of c-Rel nuclear expression as surrogate of c-Rel activation in 460 patients with de novo DLBCL. Nuclear c-Rel expression, observed in 137 (26.3%) DLBCL patients frequently associated with extranoal origin, did not show significantly prognostic impact in the overall- or germinal center B-like-DLBCL cohort, likely due to decreased pAKT and Myc levels, up-regulation of FOXP3, FOXO3, MEG3 and other tumor suppressors coincided with c-Rel nuclear expression, as well as the complicated relationships between NF-kappaB members and their overlapping function. However, c-Rel nuclear expression correlated with significantly poorer survival in p63+ and BCL-2- activated B-cell-like-DLBCL, and in DLBCL patients with TP53 mutations. Multivariate analysis indicated that after adjusting clinical parameters, c-Rel positivity was a significantly adverse prognostic factor in DLBCL patients with wild type TP53. Gene expression profiling suggested dysregulations of cell cycle, metabolism, adhesion, and migration associated with c-Rel activation. In contrast, REL amplification did not correlate with c-Rel nuclear expression and patient survival, likely due to co-amplification of genes that negatively regulate NF-kappaB activation. These insights into the expression, prognostic impact, regulation and function of c-Rel as well as its crosstalk with the p53 pathway underscore the importance of c-Rel and have significant therapeutic implications

Loss of PRDM1/BLIMP-1 function contributes to poor prognosis of activated B-cell-like diffuse large B-cell lymphoma

PRDM1/BLIMP-1, a master regulator of plasma-cell differentiation, is frequently inactivated in activated B-cell-like (ABC) diffuse large B-cell lymphoma (DLBCL) patients. Little is known about its genetic aberrations and relevant clinical implications. A large series of patients with de novo DLBCL was effectively evaluated for PRDM1/BLIMP-1 deletion, mutation, and protein expression. BLIMP-1 expression was frequently associated with the ABC phenotype and plasmablastic morphologic subtype of DLBCL, yet 63% of the ABC-DLBCL patients were negative for BLIMP-1 protein expression. In these patients, loss of BLIMP-1 was associated with Myc overexpression and decreased expression of p53 pathway molecules. In addition, homozygous PRDM1 deletions and PRDM1 mutations within exons 1 and 2, which encode for domains crucial for transcriptional repression, were found to show a poor prognostic impact in patients with ABC-DLBCL but not in those with germinal center B-cell-like DLBCL (GCB-DLBCL). Gene expression profiling revealed that loss of PRDM1/BLIMP-1 expression correlated with a decreased plasma-cell differentiation signature and upregulation of genes involved in B-cell receptor signaling and tumor-cell proliferation. In conclusion, these results provide novel clinical and biological insight into the tumor-suppressive role of PRDM1/BLIMP-1 in ABC-DLBCL patients and suggest that loss of PRDM1/BLIMP-1 function contributes to the overall poor prognosis of ABC-DLBCL patients

Age cutoff for Epstein-Barr virus-positive diffuse large B-cell lymphoma--is it necessary?

Contains fulltext : 153699.pdf (publisher's version ) (Open Access)Epstein-Barr virus-positive diffuse large B-cell lymphoma of the elderly (EBV+ DLBCL-e) is a molecularly distinct variant of DLBCL, characterized by a monoclonal B-cell proliferation that occurs in patients >50 years of age without a history or clinicopathologic evidence of immunodeficiency. However, patients with EBV+ DLBCL younger than 50-years-old also exist in Western countries. We evaluated the clinicopathologic, immunophenotypic and genetic features in Cacausian patients with EBV+ DLBCL who are 50 years. In patients who are 50 years, common expression of CD30, p50, pSTAT3 and less frequent expression of BCL6 were observed. Older patients also more commonly had a poor performance status (ECOG>/=2). Comparing EBV+ DLBCL patients in 50 years, both groups had similar clinicopathologic, immunophenotypic and genetic features. Gene expression profiling, microRNA profiling and treatment outcome of the younger patients with EBV+ DLBCL was not distinctive from tumors in older patients. Based on our data, we suggest that the arbitrary age cutoff for EBV+ DLBCL is unnecessary and should be eliminated in the WHO lymphoma classification scheme