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 IgMkappa. 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. (C) 2002 by The American Society of Hematology.