Monocytoid B-cell lymphoma in a patient with human immunodeficiency virus infection. Demonstration of human immunodeficiency virus sequences in paraffin-embedded lymph node sections by polymerase chain reaction amplification.

There is a significantly increased incidence of malignant lymphoma in patients with acquired immunodeficiency syndrome (AIDS). The lymphomas are usually of a high grade and of B-cell phenotype. While the frequent presence of reactive monocytoid B lymphocytes in patients with AIDS-related lymphadenopathy has recently been documented in several studies, to our knowledge, there are no reported cases of monocytoid B-cell lymphoma, the neoplastic counterpart of monocytoid B lymphocytes, in patients with AIDS. We now describe a human immunodeficiency virus (HIV)-positive patient with HIV-related lymphadenopathy in whom monocytoid B-cell lymphoma developed during the course of his disease. The morphologic and immunologic features of the lymphoma were characteristic of monocytoid B-cell lymphoma, and the involved lymph node exhibited a reversed CD4/CD8 ratio. Moreover, using the polymerase chain reaction, we were able to demonstrate HIV genome in DNA extracted from the lymph node tissue. To our knowledge, this is the first report of a case of monocytoid B-cell lymphoma occurring in an HIV-positive patient and in which we were able, by using a sensitive molecular biologic technique, to demonstrate HIV sequence in paraffin-embedded, fixed lymph node sections.