Intestinal lymphoma in a patient with chronic lymphocytic leukemia of atypical phenotype: Richter's syndrome of unusual presentation.

A patient who developed an intestinal large-cell pleomorphic lymphoma during the course of untreated chronic lymphocytic leukemia (CLL) with an atypical phenotype (SIgG kappa) is reported. This is an unusual presentation of Richter's syndrome since RS with primary gastrointestinal involvement has only been described in two patients. In our case, immunological studies disclosed the same immunoglobulin (IgG kappa) in the large-cell pleomorphic lymphoma and on the surface of CLL cells, suggesting that both had arisen from the same clonal proliferation.