A close surgical margin after radical prostatectomy is an independent predictor of recurrence

The term close surgical margin refers to a tumor extending to the inked margin of the specimen without reaching it. Current guidelines state that a close surgical margin should simply be reported as negative. However, this recommendation remains controversial and relies on limited evidence. We evaluated the impact of close surgical margins on the long-term risk of biochemical recurrence after radical prostatectomy.

We identified 1,195 consecutive patients who underwent radical prostatectomy and lymphadenectomy for localized prostate cancer at our institution from 1993 to 1999. In 894 of these patients associations between margin status and location, Gleason score, pathological stage, preoperative prostate specific antigen, prostate weight and age with the risk of biochemical recurrence were examined.

Of these 894 patients 644 (72%) had negative margins and of these patients 100 (15.5%) had close surgical margins. In the group with prostate specific antigen failure, median time to recurrence was 3.5 years. In the group without recurrence median followup was 9.9 years. Cumulative recurrence-free survival differed significantly among positive, negative and close surgical margins (p <0.001). On multivariate analysis a close surgical margin constituted a significant, independent predictor of recurrence (HR 2.1, 95% CI 1.04-4.33). Gleason score and positive margins were the strongest prognostic factors.

In this cohort close surgical margins were independently associated with a twofold risk of postoperative biochemical recurrence. Further evaluation of the clinical significance of close surgical margins is indicated as they might be an indicator of local recurrence and of relevance when considering salvage therapy.