Impact of positive surgical margins on prostate cancer recurrence and the use of secondary cancer treatment: data from the CaPSURE database.

Purpose: We determined the impact of positive surgical margins on prostate specific antigen (PSA) recurrence and secondary treatment in patients who underwent radical prostatectomy as definitive local treatment for prostate cancer.
Materials and Methods: We reviewed the pathology reports of 1,383 patients in the CaPSURE database, a longitudinal disease registry of men with prostate cancer, who underwent radical prostatectomy as definitive local treatment. Pathological stage, Gleason score, and the number and location of any positive surgical margins were determined in each patient. PSA recurrence was defined as PSA 0.2 ng./ml. or greater on 2 consecutive occasions after radical prostatectomy. Secondary cancer treatment consisted of radiation or androgen deprivation after radical prostatectomy. Adjuvant and nonadjuvant secondary treatment was given within and more than 6 months after radical prostatectomy, respectively. Kaplan-Meier event rates of PSA recurrence and secondary treatment were calculated for patients with positive and negative surgical margins. We performed multivariate Cox proportional hazards analysis to adjust for clinical differences in groups.
Results: Patients with positive surgical margins were significantly more likely to undergo secondary adjuvant or nonadjuvant cancer treatment and have PSA recurrence than those with negative margins. After adjusting for patient age, ethnicity, PSA at diagnosis, pathological stage and Gleason score, surgical margin status was an important independent predictor of PSA recurrence and secondary treatment (p = 0.06 and 0.0011, respectively). The number of positive margins and positive margin location had little impact on the outcomes measured.
Conclusions: These data indicate that surgical margin status is an independent predictor of PSA recurrence and secondary cancer treatment in patients who underwent radical prostatectomy as definitive local therapy for prostate cancer.