During the period from 1981 through 1984, 14 immunocompromised homosexual males with intermediate or high-grade non-Hodgkin's lymphoma were seen at University of Texas M.D. Anderson Hospital and Tumor Institute. Six patients had diffuse large-cell lymphoma, seven had diffuse undifferentiated lymphoma, and one had unclassifiable lymphoma that suggested large-cell lymphoma. Eight patients had the acquired immunodeficiency syndrome (AIDS) and five had the AIDS-related complex. Kaposi's sarcoma was initially present in four patients and developed later in two others. The patients with diffuse large-cell lymphoma were characterized by more severely altered immune parameters, multicentric brain mass lesions, pretherapy opportunistic infections, lower performance status, poor response to therapy, and death in all within six months. The undifferentiated lymphoma group had preceding generalized reactive lymphadenopathy, less severe immune dysfunction, and excellent response to combination chemotherapy, with survival time greater than 19 months in three patients. Twelve of the patients had extranodal sites of lymphoma at presentation. There is a definite trend for the development of aggressive non-Hodgkin's lymphomas with unusual sites of extranodal involvement in immunocompromised homosexual males, with the potential for good tolerance to combination chemotherapy and improved survival in the subgroup without severe concomitant opportunistic infections.