CD5(-) B-Cell lymphoproliferative disorders presenting in blood and bone marrow - A clinicopathologic study of 40 patients

We studied 40 patients with CD5(-) B-cell lymphoproliferative disorders (B- LPDs) presenting in blood or bone marrow and 28 control patients with CD5() B-cell chronic lymphocytic leukemia (CLL). Fifteen study patients had mor phologic features typical of CLL. The 15 patients with CD5(-) CLL were olde r and had lower absolute lymphocyte counts and more advanced-stage disease at diagnosis than controls. Ten study patients had morphologic features sug gesting mantle cell lymphoma (MCL); 3 were Eater given a diagnosis of MCL b ased on lymph node biopsy results. The 10 patients with CD5(-) MCL were old er and at a more advanced stage than CLL control patients. The remaining 15 study patients were given the following diagnoses: circulating non-Hodgkin lymphoma, 5; splenic lymphoma with villous lymphocytes, 5; lymphoplasmacyt oid lymphoma, 3; and CLL/ pro-lymphocytic leukemia, 2. For the patients wit h CD5(-) B-LPDs with morphologic features and manifestations resembling CLL , we prefer the term CD5(-) CLL variant because of clinical and immunopheno typic differences. Patients with CD5(-) B-LPDs with atypical nuclear morpho logic features may represent the leukemic phase of MCL. Since CD23 is expre ssed in most patients with CD5(-) B-LPD, its use in subclassifying these di sorders seems limited.