Somatically mutated immunoglobulin IGHV@ genes without intraclonal heterogeneity indicate a postgerminal centre origin of primary intraocular diffuse large B-cell lymphomas

Abstract

Primary intraocular lymphoma (PIOL) is a type of diffuse large B-cell lymphoma (DLBCL) that is related to primary central nervous system lymphoma (PCNSL). Whether their pathogenesis is similar is presently unknown. Immunoglobulin heavy chain variable genes (IGHV@) somatic mutations were analysed in five patients with PIOL, one patient with concomitant PCNSL and one patient with systemic DLBCL involving the eye. Six in-frame mutated clonal IGHV@ rearrangements were cloned from PIOL specimens. The sequences showed no evidence of antigen selection and revealed absence of intraclonal heterogeneity in four of five cases, suggesting that PIOL and PCNSL may differ in their ontogeny. © 2007 The Authors.