In patients with follicular lymphoma treated with single-agent rituximab, single nucleotide polymorphisms in the FCGR3A gene are known to influence response and progression-free survival. The prognostic role of FCGR3A and FCGR2A polymorphisms in patients with follicular lymphoma treated with rituximab and chemotherapy combination remains controversial and has not been evaluated in the context of rituximab maintenance. FCGR3A and FCGR2A single nucleotide polymorphisms were evaluated in, respectively, 460 and 455 patients treated in the PRIMA study to investigate whether these were associated with response rate and patient outcome after rituximab chemotherapy induction and 2-year rituximab maintenance. In this representative patient cohort, complete and unconfirmed complete responses after rituximab chemotherapy were observed in 65%, 67%, 66% (P ؍ .86) and 60%, 72%, 66% (P ؍ .21) of FCGR3A VV, VF, FF and FCGR2A HH, HR, RR carriers, respectively. After 2 years of rituximab maintenance (or observation), response rates did not differ among the different genotypes. Progression-free survival measured from either treatment initiation or randomization to observation or maintenance was not influenced by these polymorphisms. These data indicate that FCGR3A and FCGR2A polymorphisms do not influence response rate and outcome when rituximab is combined with chemotherapy or used as maintenance treatment. The PRIMA study is registered at www.clinicaltrials.gov as NCT00140582. (Blood. 2012;120(13):2650-2657)
IntroductionThe prognosis of patients with follicular lymphoma (FL) remains variable, and the natural history of this lymphoma is typified by multiple episodes of relapse. 1 Despite a relatively long overall survival (OS), advanced stage FL generally remains an incurable disease. To more accurately predict a patient's prognosis, a variety of scores that are based on presenting clinical and simple biologic characteristics, such as the follicular lymphoma international prognostic index (FLIPI) score, have been proposed. 2 The decision to initiate treatment is usually determined by the presence of a clinically significant tumor mass, hematopoietic compromise, or symptomatic disease. 3 Recent biologic data have suggested that the host-tumor interaction may influence disease behavior, and assessment of specific cellular components within the tumor microenvironment may provide additional prognostic information. 4 The outcome of patients could also be influenced by inherent host immunologic factors. For example, recent studies have shown that the prognosis of patients with FL was associated with germline polymorphisms in immune-response elements, such as the cytokine genes IL1RN, IL2, IL8, and IL12. 5 The prognosis of patients with FL has dramatically improved with the introduction of anti-CD20 monoclonal antibodies (mAbs). [6][7][8][9] The therapeutic activities of these mAbs may also be affected by patient biologic characteristics such as polymorphisms in FcG receptors (FC␥R) genes. 10 The affinity of the Fc portion of anti-C...