CLINICAL OBSERVATIONS, INTERVENTIONS, AND THERAPEUTIC TRIALS De novo CD5 diffuse large B-cell lymphoma: a clinicopathologic study of 109 patients

De novo CD5 diffuse large B-cell lymphoma (CD5 DLBCL) is known to have phenotypically and genotypically different characteristics than CD5 DLBCL and mantle cell lymphoma (MCL). To further characterize CD5 DLBCL, 109 patients with CD5 DLBCL were reviewed, and the results were compared with those of 384 CD5 DLBCL and 128 cyclin D1 MCL patients. Patients with CD5 DLBCL showed a higher age distribution (median, 66 years; P .0083) and a female predominance (male-female ratio, 49:60, P .011) compared with those with CD5 DLBCL. CD5 DLBCL was more closely associated with many aggressive clinical features or parameters than CD5 DLBCL: 69% older than 60 years (P .039), 34% with performance status greater than 1 (P .0016), 69% with serum lactate dehydrogenase level higher than normal (P < .0001), 62% with stage III/IV disease at diagnosis (P .0023), 35% with more than one extranodal site (P .023), and 40% with B symptoms (P .0031). The overall International Prognostic Index score was thus significantly higher for the patients with CD5 DLBCL than for those with CD5 DLBCL (P .00005). The most frequent site of extranodal involvement was bone marrow (28%), a higher frequency than that for CD5 DLBCL (P < .0001) but lower than that for cyclin D1 MCL (P .0015). Histopathologically, CD5 DLBCL showed centroblastic morphology except for 3 patients with immunoblastic disease, and interfollicular growth pattern (7%) and intravascular or intrasinusoidal infiltration (19%) were observed. Immunophenotypically, CD5 DLBCL was characterized by a CD5 CD10 CD19 CD20 CD21 CD23 cyclin D1 phenotype and a predominance of surface IgM . Of particular interest is that CD5 DLBCL was characterized by a survival curve significantly inferior to that for patients with CD5 DLBCL (P .0026). These findings suggest that CD5 DLBCL may constitute a unique subgroup of DLBCL. (Blood. 2002;99:815-821)