T-cell-rich B-cell lymphoma: a clinicopathologic study of eight cases

T-cell-rich B-cell lymphoma (TCRBCL) is a recently recognized and ill-defined form of non-Hodgkin's lymphoma (NHL), with no generally accepted diagnostic criteria and with limited information regarding its incidence, cellular origin, morphologic spectrum and biologic behavior. The recent findings suggest that TCRBCL could be a biologically distinct disease characterized by male preponderance, advanced-stage disease initially and high incidence of extranodal localization, especially in the bone marrow. For the time being, proper diagnosis rests on the immunohistochemical identification of the scattered large malignant B-cells amid a sea of small reactive T-lymphocytes. In this study, the clinicopathologic features of 8 patients (pts) with TCRBCL are presented. The male to female ratio was 5/3, and the median age was 52 years (32-67). The disease was advanced in most patients: 5 pts with stage IV and 2 pts with stage III. The patients presented with generalized lymphadenopathy (5), splenomegaly and/or hepatomegaly (4) and bone marrow involvement (4). The diagnosis of TCRBCL was initially established in 6 pts, while the remaining 2 pts were initially diagnosed as having Hodgkin's disease (of mixed cellularity in 1 pt and lymphocytic predominance in another). Revision of the 2 samples comprising immunohistochemistry enabled diagnosis of TCRBCL. Immunohistomorphologically the present series can be differentiated from other types of lymphoma such as lymphocyte-predominant Hodgkin's disease and peripheral T-cell lymphoma.