Cutaneous B-cell lymphoma. An unusual presentation

A patient presented with the clinical and some of the histopathologic findings consistent with a cutaneous T-cell lymphoma. Immunophenotyping, however, clearly demonstrated the B-cell nature of the proliferation. This report emphasizes the importance of immunophenotyping in these lesions, particularly since only these studies can definitely characterize these proliferations. Of greater importance is that therapy, clinical course, and prognosis will vary according to the true nature of the lymphoma. The differential diagnosis of pseudolymphoma, B-cell lymphoma, and T-cell lymphoma is also discussed.