CD5- mantle cell lymphoma.
Mantle cell lymphoma (MCL) typically expresses B-cell antigens and CD5 and overexpresses bcl-1 protein. However, unusual cases of bcl-1+ and CD5-MCL have been observed, posing a practical challenge for correct diagnosis and management. We identified 25 cases (48 samples) of bcl-1+ and CD5- lymphoma. CD5 expression was assessed by flow cytometric analysis alone (1 case), immunohistochemical analysis alone (17 cases), or dual flow cytometric/immunohistochemical methods (7 cases). The morphologic features were consistent with MCL with centrocytic cytomorphology in 20 cases and blastic variant in 5 cases. The t(11;14) was confirmed in 8 of 11 cases by fluorescence in situ hybridization of paraffin-embedded tissue. Cytogenetic analysis revealed the t(11;14) within a complex karyotype in 2 additional cases. These data show that MCL may lack CD5 expression. Evaluation of bcl-1 expression by immunohistochemical analysis or molecular genetics may be indicated if MCL is suspected clinically or morphologically despite a lack of CD5 expression.
Liu
Zach
Z
IMPATH, New York, NY 10019, USA.
Dong
Henry Y
HY
Gorczyca
Wojciech
W
Tsang
Patricia
P
Cohen
Patti
P
Stephenson
Christine F
CF
Berger
Carol S
CS
Wu
C Daniel
CD
Weisberger
James
J
D000368:Aged; D000369:Aged, 80 and over; D018956:CD5 Antigens / Q000032:analysis* / Q000235:genetics; D002880:Chromosomes, Human, Pair 11; D005260:Female; D005434:Flow Cytometry; D006801:Humans; D016130:Immunophenotyping; D017404:In Situ Hybridization, Fluorescence; D020522:Lymphoma, Mantle-Cell / Q000737:chemistry / Q000235:genetics / Q000473:pathology*; D008297:Male; D008875:Middle Aged
D018956:CD5 Antigens