The Efficacy of Rituximab plus Hyper-CVAD Regimen in Mantle Cell Lymphoma Is Independent of FCγRIIIa and FCγRIIa Polymorphisms

Abstract Mantle cell lymphoma (MCL) accounts for 3-10% of all non-Hodgkin's lymphomas, with median overall survival not exceeding 3-4 years. Rituximab in combination with the Hyper-CVAD regimen appears the most promising regimen; thus, we adopted it as a first-line treatment strategy in a series of 24 patients. In addition to evaluation of clinical success of the regimen, we investigated a possible role of polymorphism in IgG Fc receptors, FCγRIIIa and FCγRIIa. The frequencies of FCγRIIIa-158 were as follows: V/V=4/24 (17%); V/F=16/24 (66%); F/F=4/24 (17%). Those of the FCγRIIa-131 polymorphism were H/H=11/24 (46%), H/R=9/24 (37%), R/R=4/24 (17%).The overall response rate was 62.5%, with 33% of complete responses (CRs) after four cycles of R-Hyper-CVAD. Two-year progression-free survival (PFS) was 78% for 158V/V patients vs 75% for cases carrying phenylalanine (p=0.88). When the FCγRIIa polymorphism was assessed, the 2-year PFS was 82% for 131H/H patients vs 75% for those carrying arginine (p=0.26).Eighty...