Primary lymphoma of the kidney in the acquired immunodeficiency syndrome.

An increased incidence of lymphoma has been reported in patients with the acquired immunodeficiency syndrome. Malignant lymphomas that develop within this setting of impaired immune surveillance have distinctive clinical, histologic, and molecular biologic characteristics. Histologically, the majority of these lymphomas are small noncleaved cell or immunoblastic lymphomas, and are B-cell phenotype by immunophenotypic and immunoglobulin gene rearrangement studies. In contrast with malignant lymphoma occurring in the general population, extranodal origin is common in acquired immunodeficiency syndrome-related non-Hodgkin's lymphomas, with the central nervous system, bone marrow, gastrointestinal tract, and liver being the most common sites. To the best of our knowledge, there has been no description in the literature of primary renal lymphoma occurring in patients with the acquired immunodeficiency syndrome. We report an unusual case of primary non-Hodgkin's lymphoma (diffuse B-cell immunoblastic type) of the kidney in a patient with the acquired immunodeficiency syndrome.