Purpose: The incidence, clinical features, laboratory findings, and treatment results of 39 patients with Richter's syndrome (RS) are reported.
Patients and methods: Thirty-nine of 1,374 patients with chronic lymphocytic leukemia (CLL) developed RS.
Results: Features associated with RS included systemic symptoms (59%), progressive lymphadenopathy (64%), extranodal involvement (41%), elevation of lactate dehydrogenase (LDH; 82%), and a monoclonal gammopathy (44%). Analysis of the CLL karyotype showed no specific chromosomal abnormality that conferred increased risk; however, multiple abnormalities were common. Patients at all Rai stages and in complete response (CR) were at risk, including three CR patients with no residual disease at the level of detection by dual-parameter flow cytometry or restriction analysis for immunoglobulin (Ig) gene rearrangements. The incidence was not higher in patients who had received prior fludarabine or chlorodeoxyadenosine. The median survival duration was only 5 months, despite multiagent therapy. Patients who responded had prolonged survival durations (P < .001). Three of eight patients who survived more than 1 year had a de novo presentation of both CLL and large-cell lymphoma (LCL). Comparison of surface light-chain analysis from both low- and high-grade components demonstrated isotypic light-chain expression in 12 of 15 patients. Ig heavy- and light-chain gene rearrangement analysis showed identical rearrangement patterns in five of five patients.
Conclusion: The clinical, laboratory, and survival characteristics of our RS patients were similar to those reported in earlier studies. Ig gene rearrangement and light-chain isotype analysis support a common origin for CLL and LCL. Despite progress in the treatment of CLL, the development of LCL remains a serious complication and continued surveillance in all CLL patients is warranted.