RADICAL PROSTATECTOMY FOR PROSTATE-CANCER - THE PERINEAL APPROACH INCREASES THE RISK OF SURGICALLY INDUCED POSITIVE MARGINS AND CAPSULAR INCISIONS

Purpose: We compare the incidence of positive surgical margins in pati ents who underwent perineal or retropubic radical prostatectomy for cl inically localized (stage T1, T2) prostate cancer. Materials and Metho ds: In this retrospective, nonrandomized study we reexamined the speci mens of 94 consecutive patients who underwent radical perineal (48) or retropubic (46) prostatectomy for clinically localized prostate cance r (stage T1, T2) and with pathological stage pT2 (intracapsular), pT3A (established extracapsular extension without positive margins) or pT3 B (extracapsular extension with positive margins) without lymph node i nvolvement (NO). We assessed the presence or absence of extracapsular cancer with or without positive margins, incisions of the prostatic ca psule exposing cancer (surgically induced positive margins) or benign glandular tissue. Patients were followed for 3 to 66 months (mean 25) using an ultrasensitive prostate specific antigen assay with a lower d etection limit of less than 0.05 ng./ml. Results: The overall incidenc e of positive margins in cancer tissue was 56% in the perineal and 61% in the retropubic group, and biochemical failure-free survival was 67 % each. However, surgically induced positive margins in patients with organ confined disease were more frequent in the perineal than retropu bic group (43 versus 29%, p <0.05) and associated with a 37% risk of b iochemical failure (prostate specific antigen greater than 0.1 ng./ml. ) at mean followup. In addition, capsular incisions exposing benign ti ssue were more frequent in the perineal than retropubic group (90 vers us 37%, p <0.05) irrespective of pathological stage. Conclusions: Alth ough overall positive margins and biochemical failure rates are simila r or identical for the perineal and retropubic approaches for organ co nfined prostate cancer, the perineal approach is associated with a sig nificantly higher risk of capsular incisions and surgically induced po sitive margins and, thus, a higher risk of biochemical failure.