Brachytherapy for recurrent prostate cancer after radiation therapy

Prostate cancer specialists routinely see patients with recurrent disease after external beam irradiation. Traditionally, only palliative treatments have been offered with hormonal intervention or simple observation. A significant, although as yet uncertain, percentage of these patients will have only locally recurrent cancer and thus are potentially candidates for curative salvage therapy. Permanent brachytherapy with (125)I or (103)Pd has been used in an attempt to eradicate the remaining prostate cancer and prevent the need for additional intervention. It is particularly critical in this population to identify those patients most likely to have distant metastases or who are unlikely to suffer death or morbidity from their local recurrence to avoid potential treatment morbidity in patients unlikely to benefit from any intervention. Review of the literature shows 5-year freedom from second relapse after salvage brachytherapy in approximately 50% of patients, although with careful case selection second relapse free survival rates of up to 83% may be achieved. A schema is presented, based on the available data, suggesting that it may be possible to identify those patients who are most likely to benefit from salvage treatment. These include men with the following: (1) histologically confirmed local recurrence, (2) no clinical or radiologic evidence of distant disease, (3) adequate urinary function (IPSS < 20), (4) age and overall health indicative of >5- to 10-year life expectancy, (5) prolonged disease-free interval (>2 years) from primary radiation therapy, (6) long prostate-specific antigen (PSA) doubling time (>6-9 months), (7) Gleason sum </=6, and (7) PSA <10 ng/mL at the time of recurrence.