Secondary CD5+ diffuse large B-cell lymphoma not associated with transformation of chronic lymphocytic leukemia/small lymphocytic lymphoma (Richter syndrome).
Few cases of secondary CD5+ diffuse large B-cell lymphoma (DLBCL) that are not Richter syndrome have been reported previously. We report 9 cases of non-Richter syndrome secondary CD5+ DLBCL. Among 529 cases of DLBCL, 38 (7.2%) were CD5+ DLBCL, including 9 of secondary CD5+ DLBCL. Five cases gained CD5 expression during the clinical course of DLBCL (group 1). Three cases showed transformation from CD5- low-grade B-cell lymphoma to CD5+ DLBCL (group 2). The remaining case showed coexistence of CD5+ DLBCL and CD5+ follicular lymphoma. The clonal relationships of CD5- and CD5+ tumors were confirmed in all 4 available cases. Cases of secondary CD5+ DLBCL that were not Richter syndrome were classifiable into 3 groups. Groups 1 and 2 showed the gain of CD5 during the clinical course or transformation of the tumors, suggesting that CD5 expression is closely associated with the progression of B-cell lymphoma.
Maeshima
Akiko Miyagi
AM
Clinical Laboratory Division, National Cancer Center Hospital, Tokyo, Japan.
Taniguchi
Hirokazu
H
Nomoto
Junko
J
Maruyama
Dai
D
Kim
Sung-Won
SW
Watanabe
Takashi
T
Kobayashi
Yukio
Y
Tobinai
Kensei
K
Matsuno
Yoshihiro
Y
D018956:CD5 Antigens / Q000096:biosynthesis*; D002471:Cell Transformation, Neoplastic; D005434:Flow Cytometry; D006801:Humans; D007150:Immunohistochemistry; D017403:In Situ Hybridization; D015451:Leukemia, Lymphocytic, Chronic, B-Cell / Q000473:pathology*; D016403:Lymphoma, Large B-Cell, Diffuse / Q000145:classification* / Q000378:metabolism* / Q000473:pathology*; D016133:Polymerase Chain Reaction
D018956:CD5 Antigens