The impact of FcγRIIa and FcγRIIIa gene polymorphisms on responses to RCHOP chemotherapy in diffuse large B-cell lymphoma patients.

Rituximab is a monoclonal antibody routinely used in the treatment of B-cell non-Hodgk in lymphomas. It mediates antibody-dependent cellular cytotoxicity of B lymphocytes by bridging them with Fc gamma receptors (Fc gamma R) on effector cells. Several polymorphisms in the Fc gamma R genes have been identified to influence rituximab binding to Fc gamma R, thus altering its antitumor effect in indolent lymphomas. In the present study, the impact of Fc gamma RIIa and Fc gamma RIIIa polymorphisms on the survival and response to immunochemotherapy consisting of rituximab, cyclophosphamide, doxorubicin, vincristine and prednisone was evaluated in diffuse large B-cell lymphoma (DLBCL) patients. A total of 29 Slovenian DLBCL patients were studied. Genotyping was conducted for Fc gamma RIIa-27, Fc gamma RIIa-131, Fc gamma RIIIa-48 and Fc gamma RIIIa-158 polymorphisms. The median follow-up time was 29.7 months (range, 9.7-45.4 months). No significant impact of the genotypes was observed on the treatment response, progression-free or overall survival of DLBCL patients. There was a non-significant trend of an improved response to chemotherapy without additional irradiation in patients homozygous for Val at Fc gamma IIIa-158 compared to Phe carriers. The findings of the present study indicate that Fc gamma R polymorphisms have no influence on the survival of DLBCL patients.