Recent studies have shown correlations between diffuse large B-cell lymphoma (DLCBL) prognosis and molecular features using genome profiles by cDNA microarrays. Since this analysis is not routinely used, immunohistochemical tests for prediction of DLBCL survival are gaining major importance, using markers as, CD10, BCL-6 and MUM-1 to identify germinal center B-cell (GCB) and non-GCB, respectively. The goal of this study was to evaluate the significant effect on survival within GCB and non-GCB subgroup.
Patients and Methods: Seventy-four untreated pts (median age: 58 yrs: 38M/36F) with DLBCL de novo diagnosed in a single institution, treated with CHOP-like regimens. Tissue microarrays (TMA) blocks were created from paraffin-embedded, formalin-fixed block and stained with antibodies to CD20 (clone L26, Dako), CD10 (clone 56C6; Novocastra; NCL-CD10-270), BCL-6 (clone GI 191E/A8; Cell Mark; CMC 798) and MUM1 (clone MUM1p; Dako, CA; M7259). Results. Cases were subclassified using CD10, BCL-6, and MUM1 expression, and 25 cases (33.8%) were considered GCB and 49 cases (66.2%) non-GCB. The 2-year overall survival (OS) for the GCB group was 80% compared with only 38.9% for the non-GCB (p<0.001). In the multivariate analysis, only the International Prognostic Index score (IPI 3-4 HR=2.6, p=0.013) and the GCB phenotype (Non-GCB HR=2.7, p=0.054) were independent prognostic factors. In summary, immunohistochemical expression of CD10, BCL-6 and MUM1 are able to determine the GCB and non-GCB subtypes of DLBCL and predict survival.
Disclosure: No relevant conflicts of interest to declare.