During the past few years the neoplasms defining the diagnosis of AIDS are in apparent evolution and a new distribution of specific tumors is currently reported in the literature. Besides the Kaposi's sarcoma, non-Hodgkin's lymphomas, and uterine cervical carcinoma, other malignancies are frequently diagnosed in HIV+ population, particularly during the advanced stages of the infection. The pathogenesis of such an increase of tumor diffusion is apparently related to the persistence of several herpes viruses including HHV8 and HPV whose molecular interaction with HIV may contribute to the genetic variations suitable for tumor development. The epidermoid anal carcinoma is a tumor whose appearance is increasingly recurrent in HIV+ patients, although it is not considered as an AIDS-defining neoplasia. This tumor is prevalent in HIV+ homosexual men, in particular during the full-blown immunodeficiency disease. Here we report the case of a patient whose diagnosis of AIDS was emphasized by the concurrent presence of the anal tumor.