Prognostic Impact of Immunohistochemical Profile and Microvessel Density (MVD) in Diffuse Large B Cell Lymphoma (DLBCL) Treated with R-CHOP
T Cardesa, G Gutierrez-Garcia, F Climent, L Arenillas, S Serrano, V Romagosa, E Gonzalez-Barca, E Campo, A Lopez-Guillermo, Ll Colomo. Hospital Clnic, Barcelona, Spain; Hospital de Bellvitge, Barcelona, Spain; Hospital del Mar, Barcelona, Grup Estudi Limfomes Catalunya i Balears (GELCAB), Spain
Background: The adittion of rituximab (R) to the classic schemes of treatment of DLBCL has significantly improved the course of the disease. As new treatments may change the known prognostic parameters it is necessary to validate them and to describe potential new ones.
Design: We have investigated the prognostic impact of germinal center (GC) and non-GC subgroups of DLBCL defined by the Hans classifier and the microvessel density (MVD) in a series of 53 de novo DLBCL treated with R-CHOP. Immunohistochemical staining for CD10, BCL6, MUM1, BCL2 and CD31 was performed on tissue microarrays. Microvessel areas, defined as CD31+ lumen areas or CD31+cell clusters, were marked and quantified using an Olympus Cell B Basic Imaging Software. For each case, MVD was assessed as the quotient of the total microvessel areas, divided by the total area of the core analyzed. A MVD above percentile 25 (p25) was considered high and a MVD below the p25 was denoted low.
Results: CD10, BCL6, MUM1, BCL2 expression and the immunohistochemical subgroups (GC and non-GC DLBCL) did not have an impact on the overall survival (OS) of the patients. However, comparing the current series with our previously cohort of patients that had not received Rituximab (Blood 2003;101:78-84), R-CHOP had a significant effect on the OS of the patients with non-GCB DLBCL (p=0.009) whereas no differences were observed in patients with GC-DLBCL. Interstingly, a low MVD was a predictive factor for better survival in patients with DLBCL treated with R-CHOP (mean OS 5.6 vs 4 years, p=0.027). Moreover, MVD also correlated with the clinical significant parameters such as the IPI score (p=0.032) and LDH (p=0.001).
Conclusions: These results suggest that treatment with R-CHOP may modify the prognostic significance of some biological markers. Moreover, patients with GCB DLBCL defined by the currently used immunohistochemical markers seem to have a scarce benefit from the use of R-CHOP, but this observation should be confirmed in further prospective studies. In addition, the role of angiogenesis in DLBCL treated with R-CHOP may be of significant interest and may have a prognostic impact.
Wednesday, March 11, 2009 9:30 AM
Poster Session V # 177, Wednesday Morning