Concern for overtreatment using the AUA/ASTRO guideline on adjuvant radiotherapy after radical prostatectomy

BACKGROUND Recently, three prospective randomized trials have shown that adjuvant radiotherapy (ART) after radical prostatectomy for the patients with pT3 and/or positive margins improves biochemical progression-free survival and local recurrence free survival. But, the optimal management of these patients after radical prostatectomy is an issue which has been debated continuously. The object of this study was to determine the necessity of adjuvant radiotherapy (ART) by reviewing the outcomes of observation without ART after radical prostatectomy (RP) in patients with pathologic indications for ART according to the American Urological Association (AUA)/American Society for Radiation Oncology (ASTRO) guideline. METHODS From a prospectively maintained database, 163 patients were eligible for inclusion in this study. These men had a pathological stage pT2-3 N0 with undetectable PSA level after RP and met one or more of the three following risk factors: capsular perforation, positive surgical margins, or seminal vesicle invasion. We excluded the patients who had received neoadjuvant hormonal therapy or adjuvant treatment, or had less than 24 months of follow-up. To determine the factors that influenced biochemical recurrence-free (BCR), univariate and multivariate Cox proportional hazards analyses were performed. RESULTS Among the 163 patients, median follow-up was 50.5 months (24.0-88.2 months). Of those men under observation, 27 patients had BCR and received salvage radiotherapy (SRT). The multivariate Cox analysis showed that BCR was marginally associated with pre-operative serum PSA (P = 0.082), and the pathologic GS (HR, 4.063; P = 0.001) was an independent predictor of BCR. More importantly, in 87 patients with pre-operative PSA < 6.35 ng/ml and GS ≤ 7, only 3 developed BCR. CONCLUSIONS Of the 163 patients who qualified for ART based on the current AUA/ASTRO guideline, only 27 (16.6%) developed BCR and received SRT. Therefore, using ART following RP using the current recommendation may be an overtreatment in an overwhelming majority of the patients.