Should a Positive Surgical Margin Following Radical Prostatectomy be Pathological Stage T2 or T3? Results From the SEARCH Database

Abstract

The finding of a positive surgical margin associated with extracapsular extension at radical prostatectomy is a poor prognostic factor. However, whether a positive surgical margin with no documented extracapsular extension portends a similarly poor prognosis is unclear. We examined the significance of the pathological features of positive surgical margin and extracapsular extension for predicting biochemical failure following radical prostatectomy. We examined data on 1,621 men from the SEARCH Database of patients treated with radical prostatectomy without lymph node metastasis. Patients were separated into 5 groups based on the pathological findings of positive surgical margin, extracapsular extension, and/or seminal vesicle invasion. Preoperative clinical variables were compared across the groups and the groups were compared for time to biochemical recurrence using Cox proportional hazards analysis. Men with seminal vesicle invasion had the highest prostate specific antigen (PSA) recurrence rates, while men with a negative surgical margin and no extracapsular extension had the lowest PSA recurrence rates. There were no differences in PSA failure rates between men with a positive surgical margin and no extracapsular extension versus men with a negative surgical margin and extracapsular extension versus men with extracapsular extension and a positive surgical margin. In this subset of patients with a positive surgical margin and/or extracapsular extension but no seminal vesicle invasion only serum PSA was a significant independent predictor of biochemical recurrence. Men with a positive surgical margin but no extracapsular extension had PSA recurrence rates similar to those in men with extracapsular extension with or without positive margins. Men with extracapsular extension had similar biochemical recurrence rates whether the surgical margin was positive or negative. If confirmed at other institutions, consideration should be given to modifying the current TNM staging system to reflect these findings.