Clinical effect of a positive surgical margin without extraprostatic extension after robot-assisted radical prostatectomy.

ABSTRACT

OBJECTIVES: The aim of this study was to investigate the effect of positive surgical margin (PSM) without extraprostatic extension after robot-assisted radical prostatectomy (RARP). MATERIALS AND METHODS: We retrospectively reviewed 837 patients who underwent RARP for clinically localized prostate cancer without neoadjuvant endocrine therapy. The pT2+category lesions were defined according to World Health Organization classification. The actuarial probabilities of biochemical recurrence-free survival (BCR-FS) were determined using Kaplan-Meier analysis. Univariate and multivariate Cox proportional hazards regression analyses were also used to identify independent predictors for BCR. RESULTS: Of the 837 patients, 102 (12.2%) experienced BCR during the follow-up period. The BCR-FS rate was significantly higher in patients with pT2+category tumors than in those with pT3a category tumors, and significantly lower in patients with pT2+category tumors than that in those with pT2 category tumors without PSM. The BCR-FS rate of patients with pT2+category tumors was significantly higher than that with pT3a category tumors with PSM but not significantly different from that with pT3a category tumors without PSM. In a multivariate analysis, the pathological T category considering pT2+category was one of independent predictive factors for BCR. CONCLUSIONS: This study support the hypothesis that the pT2+category disease is associated with a significantly increased risk of BCR in patients with organ-confined prostate cancer after RARP. As PSM can be avoided in some cases, urologists should continually seek to improve their operative skills and to reduce the rate of PSM, especially in patients with organ-confined prostate cancer.