Primary malignant lymphoma of the anorectum in homosexual men.

Two homosexual men presented with primary malignant lymphomas of the anorectum. Each patient presented with a painful mass, diagnosed by biopsy and immunologic cell marker studies. One patient, who had a reversed T4/T8 cell ratio, developed a local relapse of the tumor 11 months after radiotherapy, and Pneumocystis carinii pneumonia. The other patient, with a normal T4/T8 ratio, remained lymphoma-free and without evidence of opportunistic infection 25 months after combined chemotherapy and radiotherapy. Anorectal pathologic findings in homosexual men includes proctitis, inflammatory stricture, fissure, or anal warts. Malignant anorectal diseases, such as Kaposi's sarcoma, and cloacogenic or squamous cell carcinomas have been described in homosexual men. Primary malignant lymphoma of the anorectum is rare in both the homosexual and general populations.