CD5-positive chronic B-cell lymphoproliferative disorders: diagnosis and prognosis of a heterogeneous disease entity.
BACKGROUND
The pathology and clinical course of patients with CD5+ chronic B-cell lymphoproliferative disorders, excluding those that present with typical chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL) or mantle cell lymphoma, (i.e. CD5+B-CLPD) are poorly defined.


METHODS
We studied patients with CD5+B-CLPD to (1) more completely define the clinical features and pathology of CD5+B-CLPD, (2) compare these features to patients presenting with typical CLL, and (3) test the hypothesis that a subset of patients with CD5+B-CLPD could have a unique B-cell malignancy.


RESULTS
We identified 229 patients with CD5+B-CLPD. A definitive pathological diagnosis was made in all 61 (27%) CD5+B-CLPD patients with nonbone marrow (BM) biopsy specimens considered adequate for a comprehensive pathological examination. The most common diagnosis among these 61 patients was CLL (44%) followed by the leukemic phase of marginal zone lymphoma (34%), lymphoplasmacytic lymphoma (11%), diffuse large B cell lymphoma (8%), and high-grade B cell lymphoma not otherwise specified (2%). In contrast, among 168 patients without a non-BM tissue biopsy specimen, a specific diagnosis could be made on review of all available data in only 24 (14%) with 144 (86%) remaining "unclassified."


CONCLUSIONS
In patients with CD5+B-CLPD, a definitive diagnosis can be made on an adequate non-BM tissue biopsy suggesting that this entity does not include a novel disease. We recommend that all patients with CD5+B-CLPD should have a non-BM tissue biopsy to make a definitive diagnosis prior to initiation of treatment.
Dronca
Roxana S
RS
Division of Hematology, Mayo Clinic, Rochester, Minnesota 55905, USA.
Jevremovic
Dragan
D
Hanson
Curtis A
CA
Rabe
Kari G
KG
Shanafelt
Tait D
TD
Morice
William G
WG
Call
Timothy G
TG
Kay
Neil E
NE
Collins
Charles S
CS
Schwager
Susan M
SM
Slager
Susan L
SL
Zent
Clive S
CS
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001402:B-Lymphocytes / Q000276:immunology / Q000378:metabolism / Q000473:pathology*; D015415:Biomarkers / Q000378:metabolism; D018956:CD5 Antigens / Q000378:metabolism*; D005260:Female; D006801:Humans; D015451:Leukemia, Lymphocytic, Chronic, B-Cell / Q000175:diagnosis / Q000276:immunology / Q000378:metabolism; D016393:Lymphoma, B-Cell / Q000175:diagnosis / Q000276:immunology / Q000378:metabolism; D018442:Lymphoma, B-Cell, Marginal Zone / Q000175:diagnosis / Q000276:immunology / Q000378:metabolism; D016403:Lymphoma, Large B-Cell, Diffuse / Q000175:diagnosis / Q000276:immunology / Q000378:metabolism; D008232:Lymphoproliferative Disorders / Q000175:diagnosis* / Q000276:immunology; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D008258:Waldenstrom Macroglobulinemia / Q000175:diagnosis / Q000276:immunology / Q000378:metabolism; D055815:Young Adult
D015415:Biomarkers; D018956:CD5 Antigens