Clinicopathologic significance of immunophenotypic profiles related to germinal center and activation B-cell differentiation in diffuse large B-cell lymphoma from Chinese patients

Abstract

Diffuse large B-cell lymphoma (DLBCL) can be subdivided into prognostically significant groups with germinal center B-cell-like (GCB), activated B-cell-like (ABC), and type 3 groups. In this study, tissue microarray slides composed of 163 de novo DLBCLs from Chinese patients were immunostained for CD20, CD10, Bcl-6, MUM1, CD138, Bcl-2, Ki-67, cyclin D3, geminin, and P27(Kip1). One hundred forty-nine of 163 DLBCLs could then be classified into GCB group (pattern A), activated GCB group (pattern B) and activated non-GCB group (pattern C) according to the expression of CD10, Bcl-6, MUM1, and CD138. Of the 149 cases, 40 (26%) showed pattern A expression and were grouped as GCB group, lower than reported frequency of the studies involving mostly Western population. Compared with cases with pattern A, those with pattern B (activated GCB group) and C (activated non-GCB group) more often presented with more aggressive tumors and a shorter survival time. These results indicate that most of DLBCLs from Chinese patients can be classified into prognostically different groups based on the antigenic expression models using a panel of GCB- and ABC-associated markers. Polymerase chain reaction analysis of t(14;18) showed that 11 of 64 cases were t(14;18)-positive, and most (10 of 11) of it occurred in the group with pattern A. The translocation was significantly associated with expression of Bcl-2 protein. The group with pattern B demonstrated more frequent expression of Ki-67, cyclin D3, geminin, and showed higher proliferative activity than the group with pattern A. These findings suggest that high proliferative activity of tumors with pattern B may be associated with aggressive tumor behavior and poor clinical outcome in patients with DLBCL.