The purpose of this study was to examine trends in radical prostatectomy in New York State for the period 1991-1993. A retrospective analysis was conducted of all radical prostatectomies performed on hospitalized male Medicare beneficiaries in New York State for the period 1991-1993. Basic trend data were also analyzed for 1990. Pattern analysis was conducted on the 4,154 procedures performed between 1990-1993. In depth hospital chart review was conducted of the 220 cases of radical prostatectomy performed in patients 75 years of age and over between 1991 and 1993 and of a random sample of 263 of 1,266 patients 70-74 years of age. A total of 452 hospital charts were examined for a broad range of information, including family history and therapeutic preferences, preoperative work-up, staging, intraoperative and postoperative transfusions, postoperative complications, and mortality. The rate of radical prostatectomy dramatically rose among New York State male Medicare beneficiaries between 1990 and 1992 and remained at a high plateau in 1993. Pattern analysis revealed a tripling of the procedure rate among those 70-74 years of age and a doubling of the rate in those 75 years of age and older. It was also found that a high proportion of radical prostatectomies in men 70 years of age and older were performed by relatively few hospitals. Although rates of radical prostatectomy rose in New York State during the period under study, these rates were lower than those reported several years earlier in other parts of the country. This may reflect an overall conservative approach to the management of prostate cancer, especially among older men, on the part of New York's urologic community. The overall postoperative complication rate was 18.5% and the mortality rate 1.3%. These rates are similar to those found in other series. Prostate cancer in older men usually has a protracted course. Radical prostatectomy in such men is associated with operative risks, and significant immediate and long-term complications. In addition, the procedure provides only marginal benefit of 10 years because of competing mortality in older men. The results of this study show a need for provider and patient focused educational efforts to reduce the numbers of radical prostatectomies in older men where the benefits are marginal compared to operative risks and significant immediate and long term complications.