Follicular lymphoma can be distinguished from benign follicular hyperplasia by flow cytometry using simultaneous staining of cytoplasmic bcl-2 and cell surface CD20.
The distinction between benign follicular hyperplasia (FH) and follicular lymphoma (FL) is sometimes problematic. We wanted to determine whether the expression of bcl-2 of FH was quantitatively different from that of FL, using surface CD20 expression as a discriminator of the various lymphoid compartments. Lymph node cell suspensions from 12 cases of FH and 17 cases of FL were analyzed by flow cytometry using a combined surface CD20 and intracellular bcl-2 staining. CD20- T cells in FH demonstrated the same bcl-2 expression as the CD20+ mantle cells, but the bright CD20+ germinal center cells showed near absence of bcl-2 expression. In contrast, the neoplastic cells of FL showed greater bcl-2 expression than the T cells of the same tumors and all cell populations of FH. This difference was particularly significant between the neoplastic B cells of FL and the germinal center cells of FH. The combined analysis of CD20 and bcl-2 should be useful for the differential diagnosis between FH and FL and particularly applicable to limited samples or when B-cell clonality is in question. Whether the quantitation of bcl-2 expression can be of further discriminatory value in malignant lymphomas remains to be determined.
Cornfield
D B
DB
Department of Pathology and Laboratory Medicine, University of Florida College of Medicine, Gainesville 32610, USA.
Mitchell
D M
DM
Almasri
N M
NM
Anderson
J B
JB
Ahrens
K P
KP
Dooley
E O
EO
Braylan
R C
RC
D000911:Antibodies, Monoclonal; D018951:Antigens, CD20 / Q000032:analysis*; D003593:Cytoplasm / Q000737:chemistry; D004273:DNA, Neoplasm / Q000235:genetics; D003937:Diagnosis, Differential; D005434:Flow Cytometry; D015321:Gene Rearrangement / Q000235:genetics; D006801:Humans; D008198:Lymph Nodes / Q000473:pathology*; D008224:Lymphoma, Follicular / Q000737:chemistry / Q000175:diagnosis* / Q000235:genetics; D016133:Polymerase Chain Reaction; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000032:analysis* / Q000235:genetics; D019310:Pseudolymphoma / Q000175:diagnosis* / Q000235:genetics / Q000378:metabolism
D000911:Antibodies, Monoclonal; D018951:Antigens, CD20; D004273:DNA, Neoplasm; D019253:Proto-Oncogene Proteins c-bcl-2