Prostate cancer trends in the era of prostate-specific antigen. An update of incidence, mortality, and clinical factors from the SEER database.

Concurrent with the successful life-saving efforts in terms of prostate cancer diagnosis and treatment, some men who do not need treatment are receiving it. These are men destined to die of causes other than prostate cancer. Unfortunately, at diagnosis, men needing treatment for prostate cancer cannot be differentiated from men who do not. To make such decisions correctly for individual patients would require extremely precise measures of the time to death from prostate cancer versus when the patient would die from a competing cause. Predictive tools with this level of accuracy will never be available given the inherent uncertainty of life. At the time of prostate cancer diagnosis, the date and the cause of death for the patient are matters of weak statistical speculation. Unless the date of death from prostate cancer and the date of death from non-prostate cancer causes can be precisely determined for each patient, some men will always be overtreated or undertreated. Conservative strategies result in the undertreatment of some patients who would benefit from treatment while sparing other patients unneeded treatment. Aggressive strategies result in the overtreatment of patients who do not need therapy while curing other men of prostate cancer. Both strategies are correct, but only some of the time. Better methods of determining the length of life and cause of death may improve this situation, but not by much. [figure: see text] Dramatic shifts in the incidence, grade, stage, and age of men with prostate cancer have been observed with the advent of widespread PSA-based cancer detection in the United States. Grade and stage trends suggest that more biologically relevant (the shift from well-differentiated to moderately differentiated tumors) and yet therapeutically amenable (earlier stage) tumors have been identified in large numbers of patients during the PSA era. Clearly many men have been diagnosed and treated who will not benefit from such treatment. The relative mix of these two groups of men is not known. Given the long delay between treatment and mortality that is inherent in prostate cancer (Fig. 14), the full effects of treatment on prostate cancer mortality are probably not yet seen in prostate cancer mortality data.