title: Gastrointestinal and hepatobiliary neoplasms in AIDS.
abstract: There is an increased frequency of Kaposi's sarcoma and non-Hodgkin's lymphomas in patients with AIDS. These "opportunistic malignancies" establish the diagnosis of AIDS in an HIV-positive patient and are associated with a high likelihood of gastrointestinal and hepatobiliary involvement. Kaposi's sarcoma is a multicentric cutaneous spindle-cell tumor that is associated with luminal lesions in at least 40 per cent of patients. Gastrointestinal KS is usually asymptomatic but may rarely bleed or obstruct. Treatment of KS with either radiation or chemotherapy can reduce tumor bulk, without affecting survival. Non-Hodgkin's lymphomas in AIDS are B-cell neoplasms composed of either noncleaved or blast cells, similar to those seen in Burkitt's lymphoma. The tumors are usually highly aggressive and present in extranodal sites in the majority of cases. Primary or secondary gastrointestinal involvement is frequent, with hepatic and rectal tumors being particularly common. Unlike KS, gastrointestinal lymphomas are usually symptomatic. Obstruction, perforation, and bleeding can occur in patients with luminal involvement. Jaundice due to hepatic infiltration or biliary obstruction may be seen. Treatment with chemotherapy is usually indicated because of the rapid progression of the tumor, although no prolongation of survival has been demonstrated. There may also be an increased incidence of Hodgkin's disease and anorectal neoplasia in patients with AIDS; however, these malignancies do not establish the diagnosis of AIDS in an HIV-positive patient.
mesh_terms: D000163:Acquired Immunodeficiency Syndrome / Q000150:complications*; D001661:Biliary Tract Neoplasms / Q000209:etiology*; D005770:Gastrointestinal Neoplasms / Q000209:etiology*; D006801:Humans; D008113:Liver Neoplasms / Q000209:etiology*; D008228:Lymphoma, Non-Hodgkin / Q000209:etiology*; D012514:Sarcoma, Kaposi / Q000209:etiology*