[Rinsho Byori 50 :, 2002]

[Rinsho Byori 50 : 906～911, 2002]

Sub-Classification of Diffuse Large B-Cell Lymphoma
by Semi-Quantification of the CD5 Expression with Flow Cytometric Analysis

Noriko MANABE*1, Genji YAMAOKA*2, Hiroaki OHNISHI, MD*3, Takeshi ARAI*4,
Hiromi NAKAISHI*5, Tatushi KAJIKAWA*6, Yoshitsugu KUBOTA, MD*7, Terukazu TANAKA, MD*8,
Akira KITANAKA, MD*9, Masato WAKI, MD*10, Kimihiro KAWAKAMI, MD*11,
Masami NAGAI, MD*12, Toshihiko ISHIDA, MD*13 and Tomohiko TAMINATO, MD*14

CD5＋diffuse large B-cell lymphoma(CD5＋DLBCL) is known to have different characteristics than CD5－DLBCL and mantle cell lymphoma(MCL). 9 patients with CD5＋DLBCL were reviewed, and the results were compared with those of 8 CD5－DLBCL and 3 cyclin D1＋ MCL patients. CD5＋DLBCL was more closely related to many aggressive clinical features or parameters than CD5－DLBCL : 67% of the patients were older than 60 years, 67% with performance status ≧2, 89% with serum lactate dehydrogenase level higher than normal, 78% with stage III/IV disease at diagnosis, and 78% with more than one extranodal lesion. The overall International Prognostic Index score for the patients with CD5＋ DLBCL was thus sig-nificantly higher than that for those with CD5－DLBCL.
Immunophenotypically, CD5＋DLBCL was characterized by CD5＋CD10－CD19＋CD20＋CD21－CD23－cyclin D1－phenotype and the predominant expression of surface IgM. Of particular interest is that the survival rate of CD5＋DLBCL patients was significantly inferior to that of patients with CD5－DLBCL. To further characterize CD5＋DLBCL, we semi-quantified the CD5 expression in DLBCL cells. Our findings suggest that CD5＋DLBCL may constitute a unique subgroup of DLBCL and, moreover, CD5＋DLBCL may consist of several subgroups.

*1Department of medical technology Kagawa Prefectural College of health sciences, Kida-gun, kagawa-pref. 761-0123