Pathogenesis of non-AIDS-defining cancers: A review

As the AIDS epidemic advances, the number of HIV-infected subjects developi ng AIDS-related neoplasms is rapidly increasing, and the spectrum of malign ancies encountered is expanding. Several non-AIDS-defining cancers are bein g reported at an increasing incidence in HIV-infected individuals, includin g anal, skin, oral mucosa, head and neck and lung carcinomas, testicular tu mors, and pediatric soft-tissue sarcoma. There appears to be an emerging ro le for various concurrent viral infections in the HIV-infected host that ar e likely implicated in the pathogenesis of some nondefining-AIDS neoplasms. Our recent findings in HIV-associated lung cancers and in the precursor le sions of cervical carcinoma suggest that widespread genomic instability, as manifested by the development of increased numbers of microsatellite alter ations (MAs), may occur frequently in HIV-associated tumors and they may pl ay an important role in the pathogenesis of those neoplasms. Although the m echanism underlying the development of increased MAs is unknown, it may pla y a crucial role in the development of many HIV-associated tumors. It will be important to track the epidemiological and biological features of non-AI DS-defining cancers in HIV-infected patients, and compare them to those tum ors in the general population. It is likely that further clues about malign ant transformation and oncogenesis unraveled in the HIV setting will have b road clinical implications.