The Impact of Positive Surgical Margins on Biochemical Recurrence after Radical Retropubic Prostatectomy

Cho, Kang Su; Hong, Sung Joon; Chung, Byung Ha

Abstract

PURPOSE: We evaluated the impact of positive surgical margins as an independent predictive factor for biochemical recurrence after radical retropubic prostatectomy.
MATERIALS AND METHODS
Data on 122 patients who underwent radical prostatectomy during the last eight years were retrospectively analyzed with respect to the incidence, number, and sites of positive surgical margins, as well as biochemical recurrence. Biochemical recurrence was defined as a serum prostate-specific antigen (PSA) level of 0.2ng/ml or greater and rising on at least two postoperative measurements. The mean follow-up was 33.4 months (6.0-104.0).
RESULTS
Surgical margins were positive in 51 patients (41.8%), of whom 35 (68.6%) and 16 (31.4%) had positive margins of 1 and more than 1, respectively. The most frequent site of positive margin was the apex/ urethra, and the other frequent sites were bladder neck, posterior, anterior, and lateral portion in order of frequency. The overall biochemical recurrence rate was 35.2% (43 patients). The time to recurrence was significantly shorter in patients with positive margins than in patients with negative margins (p<0.05). Five-year recurrence-free probability was 29.5% and 74.7% in the group with positive margins and in the group with negative margins, respectively. However, the number of positive margins did not seem to have a significant influence on disease recurrence (p>0.05). We could not identify the site that showed a significant influence on biochemical recurrence compared to other sites (p>0.05). Finally, the multivariate Cox proportional hazards analyses revealed that the presence of positive margins was independently associated with time to recurrence(p<0.05).
CONCLUSIONS
Our data indicate that the surgical margin status is an independent predictor of biochemical recurrence. However, longer follow-ups and a larger sample size are necessary to understand the influence of positive margins on survival. In addition, improvement in surgical technique, which can avoid positive margins, is required.