Analysis of immunoglobulin VH genes in CD10-positive diffuse large B-cell lymphoma

Molecular, cytogenetic, and immunophenotypic characterization of follicular lymphoma grade 3B; a separate entity or part of the spectrum of diffuse large B-cell lymphoma or follicular lymphoma?

We studied a histological homogeneous group of 29 cases with the diagnosis of follicular lymphoma (FL) grade 3B (FL3Bs). In a previous study, we subdivided this group in 3 subgroups based on (1) aberrations of the 3q27 region, (2) lack of 3q27 and t(14;18), and (3) the presence of a t(14;18). In this study, we further characterized the FL3B lymphomas that are currently part of the spectrum of FL in the WHO classification, taking into account other cytogenetical aberrations, immunohistochemistry for P53, bcl2, bcl6, and CD10, rearrangement of the proto-oncogene myc, and mutation of the tumor suppressor gene TP53. With respect to P53, bcl2, bcl6 expression, myc rearrangement, and TP53 mutation, FL3B represents a homogeneous group. CD10 expression and gain of chromosome 7, considered to be typical FL markers, were more common in the FL3B t(14;18)-positive subgroup. The lack of CD10 expression and gain of chromosome 7 in most cases in the other 2 subgroups suggest that those cases have a closer relation to diffuse large B-cell lymphomas.

CD10 expression in diffuse large B-cell lymphomas does not influence survival

CD10 expression is considered as a marker of centrofollicular-derived diffuse large B-cell lymphomas (DLBCL). The aim of our study was to determine retrospectively among 98 patients with DLBCL, enrolled in the LNH93 trial of the Groupe d'Etude des Lymphomes de l'Adulte (GELA) and homogeneously treated with high-dose cyclophosphamide, doxorubicin, vincristine and prednisone (CHOP)-like regimen [doxorubicin, cyclophosphamide, vindesine, bleomycin and prednisone (ACVBP)], the expression of CD10 using immunohistochemistry and its correlation with morphological features and clinical parameters. Of the 98 patients studied, 33 (34%) expressed CD10. There was no correlation among clinical parameters, International Prognostic Index risk groups and CD10 expression, with the exception of lactic dehydrogenase levels, which were lower in CD10-negative cases (P=0.005). There was no significant correlation between CD10 expression and morphological subtyping of DLBCL. Indeed, centrofollicular-derived DLBCL may present with numerous immunoblasts or as an immunoblastic lymphoma. Overall survival rate and event-free survival were not significantly different according to CD10 expression (P=0.44 and P=0.34 respectively). Therefore, it appears that CD10 expression does not influence survival or event-free survival in DLBCL.