Immunotherapy in genitourinary neoplasia.

The putative role of the immune response in the natural defense against neoplasia remains poorly defined. Correspondingly, its potential recruitment as a means of cancer therapy has remained unfulfilled. The intricate interactions of immune response mechanisms as well as the heterogeneity of tumor cells themselves have contributed to this situation. Moreover, the immunosenescence that occurs during aging may have further compromised potential means of recruiting immune response mechanisms in treating cancer. The various attempts to treat different types of genitourinary neoplasia are illustrations of these difficulties, and emphasize directions that may need attention in future therapeutic efforts.