Prostate-specific antigen nadir of 0.5 ng/ml or less defines disease freedom for surgically staged men irradiated for prostate cancer

This report describes treatment results of men with prostate cancer staged with a pelvic lymph node dissection. Disease freedom was defined by a prostate-specific antigen (PSA) level nadir of 0.5 ng/mL or less. Since 1984, 363 men with clinical Stage T1 or T2, surgical stage node-negative prostate cancer were simultaneously irradiated with a retropubic iodine 125 prostate implant followed by external-beam radiation. The average pretreatment PSA level was 13.6 ng/mL (median 8.5, range 0.3 to 188). Disease freedom was defined as the achievement and maintenance of a nadir of 0.5 ng/mL or less. Treatment failure was defined as a nadir of more than 0.5 ng/mL or a PSA rise above this level. The median follow-up is 5 years (average 5.5, range 1 to 12.5). For all men, the 5- and 10-year disease-free survival results are 78% and 65%. Of 201 men with a minimum 5-year follow-up, 140 (70%) are disease free. The 5-year disease-free survival rate by pretreatment PSA is 4.0 ng/mL or less, 93%; 4.1 to 10.0 ng/mL, 87%; 10.1 to 20.0 ng/mL, 72%; and greater than 20.0 ng/mL, 45%. The 10-year disease-free survival results of retropubic implantation, a technique considered a failure by many investigators, followed by external-beam radiation appear to be better than either technique given separately and are comparable to the results following radical prostatectomy. These results are valuable because they form a baseline that may be improved upon in the future by simultaneous irradiation using the transperineal implant technique.