CD5 positivity in B-cell lymphoproliferative disorders (LPD) is usually considered characteristic of either chronic lymphocytic leukemia (CLL) or mantle cell lymphoma (MCL). However, other neoplastic B-LPDs may express CD5, albeit infrequently. In this study we have reviewed the tissue pathology of CD5+ B-LPDs that do not fulfill diagnostic criteria for CLL or MCL on flow cytometric studies of peripheral blood or bone marrow. Our results indicate that although CD5 positivity is most commonly associated...