Successive B-cell lymphomas mostly reflect recurrences rather than unrelated primary lymphomas.

Objectives: To address whether successive B-cell lymphomas, diagnosed within a 5- to 15-year interval, are recurrences or unrelated primary lymphomas. Methods: Immunoglobulin heavy and kappa light chain gene rearrangements were studied using multiplex polymerase chain reaction fragment assays and sequence analysis in 61 patients. Results: Clonal patterns of the multiple lymphomas from 36 patients were determined and classified accordingly: 30 recurrences, 2 possible recurrences, 2 different clones with a common origin, and 2 unrelated primary lymphomas. Conclusions: Regardless of subtype, 89% to 94% of late B-cell lymphoma relapses were recurrences of the primary tumor. Therefore, routinely investigating the possible clonal relationship between successive lymphomas may not be warranted except for specific lymphoma subtypes such as diffuse large B-cell lymphomas.