POSITIVE SURGICAL MARGINS WITH RADICAL PROSTATECTOMY - DETAILED PATHOLOGICAL ANALYSIS AND PROGNOSIS

Objectives. To examine the extent and location of positive surgical ma rgins and their influence on progression. Methods. Two hundred fifteen consecutive radical prostatectomy specimens, using 2 to 3-mm step-sec tions, were reviewed. Particular attention was paid to the location an d extent of positive margins. Seventy-three patients (34%) with one or more positive margins were subjected to further detailed analysis. Pr ogression was defined as a serum prostate-specific antigen level great er then 0.1 ng/mL and rising. The mean followup period was 23.2 months ; median 24 months (range 3 to 40). Results. Margin-positive patients had a significantly higher biopsy tumor grade (P = 0.05) than did marg in-negative patients. Capsular perforation was present in 75%, seminal vesicle invasion in 33%, and nodal metastases in 10% of margin-positi ve patients; in contrast, these tumor characteristics were present in 47%, 8%, and 1% of margin-negative patients, respectively. The extent of involvement-of inked margins was focal in 22% and extensive in 66%. An equivocal positive margin identified as surgical incision into the specimen (due to hemostatic staples, surgical dissection, or retracti on) was present in 12%. Seventy-one percent-of patients had a positive margin at only one location. Of all 99 positive-margin locations, 40% were apical, 10% anterior, 8% bladder neck, 16% posterolateral, and 2 5% posterior. Thirty-four percent of margin-positive and 7% of margin- negative patients demonstrated biochemical progression. Of the 36 pati ents with a positive margin as their only major risk factor for progre ssion (seminal vesicle and lymph node negative, Gleason score less tha n 8), 25% have progressed. Progression occurred in 2 of 9 patients wit h an equivocal positive margin, and 5 of 16 with a single focal-positi ve margin. A multivariate analysis of margin-positive patients identif ied tumor volume and grade as the most significant predictors of progr ession, with the location and extent of the positive margin not signif icant. Conclusions. Although more frequent at the prostatic apex, tumo r at the inked margin at-any location is a risk factor for postoperati ve biochemical progression.