Richter syndrome with emphasis on large-cell non-Hodgkin lymphoma in previously unrecognized subclinical chronic lymphocytic leukemia.

The authors report seven cases of Richter's syndrome, i.e. of large-cell non-Hodgkin's lymphoma (NHL) arising in association with chronic lymphocytic leukemia (CLL). Six patients had the recently recognized variant of this syndrome, occurring in patients with previously undiagnosed subclinical CLL. All patients were treated with aggressive chemotherapy and a complete response of large cell NHL was achieved in 4/7. A complete response of NHL was observed in 3 out of 6, and a partial response in 2/6 patients with simultaneous occurrence of subclinical CLL and large cell NHL (response rate 5/6). Our findings might suggest that patients with Richter syndrome occurring in previously undiagnosed subclinical CLL could represent a better prognostic group in the overall population of patients with large cell NHL transformation of CLL.