Prognostic Impact of Subclassification of Radical Prostatectomy Positive Margins by Linear Extent and Gleason Grade

Purpose: We evaluated the relationship of progression to positive surgical margin linear length and Gleason grade at a positive surgical margin.Materials and Methods: We studied 2,150 prostatectomies done for pT2 or pT3a disease to determine grade, stage and surgical margin status. In patients with positive surgical margins we recorded the location, number, positive margin linear length and highest Gleason grade at a positive margin. The Kaplan-Meier method and log rank test were used to determine differences in progression-free probability among positive margin features. The concordance index was used to discriminate the accuracy of grouping surgical margin status as negative/positive vs positive margin linear length/highest Gleason grade.Results: A total of 207 cases (10%) showed positive surgical margins, including 93 (45%) that were pT2+ and 114 (55%) that were pT3a. Patients with pT3a and positive margins had greater prostate specific antigen and tumor volume, and Gleason score 7 or greater than thos...