Impact of location and multifocality of positive surgical margins on disease-free survival following radical prostatectomy: a comparison between African-American and white men.

ABSTRACT

OBJECTIVES: Although the rate of positive surgical margins is higher in African-American men (AAM) than in white men (WM), the impact of this difference on survival is not clear. Furthermore, it is unknown whether there are racial differences in the distribution of the positive surgical margins after radical retropubic prostatectomy (RRP). We investigated the differences between AAM and WM in terms of the site and multifocality of the positive surgical margins and their effect on disease-free survival (DFS) following RRP. METHODS: Between January 1991 and December 1995, 493 patients (288 WM and 205 AAM) were treated with RRP as monotherapy. Positive surgical margins were observed in 179 patients (86 WM and 93 AAM). Patients were divided in two groups group 1 = WM and group 2 = AAM. The incidence and location of the positive surgical margins and their correlation with DFS were determined and compared. RESULTS: Overall, AAM had a higher rate of positive surgical margins than WM (48% versus 33%, respectively, P = 0.001). There was no significant difference in the frequency of multifocality of the positive margins (P = 0.4). Positive surgical margins were located significantly more often at the base in AAM (P = 0.015); however, the location of the positive surgical margins did not impact on DFS between groups. In those with multifocal positive surgical margins, AAM had a worse DFS compared with WM (P = 0.03). CONCLUSIONS: Race is an independent prognostic factor for DFS in patients with positive surgical margins. There were no differences in DFS between WM and AAM based on the margin location. In WM, prognostic factors for DFS in those with positive surgical margins were preoperative serum prostate-specific antigen, Gleason score, and pathologic stage. Conversely, in AAM none of these parameters were significant predictors of failure.