Multiple biopsies of the prostatic bed following radical prostatectomy to assess accuracy of reported resection margins.

Selected biopsies were obtained from the prostatic bed following radical prostatectomy in 35 patients with clinically localized prostate cancer in order to address and understand the high incidence of positive resection margins. The biopsies were obtained from the urethra, bladder neck and left and right posterolateral regions of the patient’s prostatic bed after the specimen was removed. Pathologically 28 out of 35 (80%) had positive resection margins, yet only five out of 35 patients (14.2%) had positive prostatic bed biopsies (residual tumors). None of the patients with negative pathological margins had positive bed biopsies. The urethra was the most common site of residual tumor. Gleason score was comparable in those with negative or positive biopsies. Tumor volume and prostatic-specific antigen level were highest in those with positive prostatic bed biopsies. We recommend routine four-point prostatic bed biopsies following radical prostatectomy.