Abstract
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. © 2010 International Clinical Cytometry Society