Immunophenotype and intermediate‐high international prognostic index score are prognostic factors for therapy in diffuse large B‐cell lymphoma patients

Abstract

The development of gene expression profiling and tissue microarray techniques have provided more information about the heterogeneity of diffuse large B-cell lymphoma (DLBCL), enabling categorization of DLBCL patients into 3 prognostic groups according to cell origin (but independently from the International Prognostic Index [IPI] score): germinal center (GCB), activated B-cell (ABC), and not classified (NC) diffuse large B-cell lymphoma. This study investigated the role of immunohistochemical discrimination between GCB and ABC&NC-DLBCL subtypes in identifying those high-risk patients who may benefit from a more aggressive first-line therapeutic approach. From February 2003 to August 2006, 45 newly diagnosed DLBCL patients, with IPI≥2, were considered eligible for this study: 13 had a GCB, 8 an ABC, and 24 a NC-DLBCL. GCB patients received 6 courses of rituximab, cyclophophosphamide, doxorubicin, vinicristine, and prednisone (R-CHOP) chemotherapy, with a subsequent, autologous stem cell transplantation in case of partial response. All ABC and NC-DLBCL patients received 6 R-CHOP cycles and autologous stem cell transplantation. Complete response rate for each treatment arm was 84.6% for GCB and 89.7% for ABC&NC-DLBCL (P = .50), with a continuous complete response rate of 81.8% and 84.6%, respectively (P = .59). Projected 4-year overall survival is 100% for GCB and 82% for ABC&NC patients (P = .12). Progression-free survival is 77% and 79% (P = .7), respectively. The autologous stem cell transplantation consolidation in the ABC&NC-DLBCL subtypes induced the same rate of complete response (and similar progression-free survival rate) compared with GCB-DLBCL. In ABC&NC-DLBCL patients the authors observed a complete response rate of 89.7% vs. 84.6% in the GCB-DLBCL subset, without any significant difference in progression-free survival rate.