Pathologic findings in additional prostatic and periprostatic tissue removed during radical prostatectomy.

Abstract

172 Background: Additional prostatic and periprostatic tissue (PPT) can be removed during radical prostatectomy (RP) when there is concern for incomplete removal of the entire prostate gland or residual extraprostatic extension of cancer. The presence of cancer in PPT during RP is largely unknown. We analyzed the rate of positive PPT findings during RP in a community-based health system to determine the yield of PPT resection to inform future clinical practice. Methods: Retrospective review of pathology reports from 976patients undergoing RP between 1998-2011 was performed. Demographic and pathologic data were collected in an IRB-approved database. Results: Of 976 RP, 267 patients (27%) had PPT excised (median: 1, range: 1-4). Median PSA was 5.0 (IQR: 3.9-7), clinical stage was T1c in 69%, and biopsy Gleason score was 6 or lower in 39%, 7 in 52% and 8 or higher in 9%. Pathologic stage was pT2 in 85%, T3 in 13%, and LN positive in 2.6%. Among 177 bladder neck biopsies, 31% contained benign prostate and 3.4% (n=6) had adenocarcinoma. Of 37 urethral biopsies, 46% contained benign prostate and 16% (n=6) had adenocarcinoma. Of 21 prostatic apical excisions, 86% contained benign prostate and 14% (n=3) contained adenocarcinoma. Of 35 excisions of suspected residual (or fragmented) prostate (posterior-lateral, median, base, capsule, pedicle), 94% contained prostate and 0% contained adenocarcinoma. No prostate tissue or cancer was present in 15 samples labeled as “periprostatic fat” and 9 “neurovascular bundle”. Conclusions: Complete excision of adenocarcinoma during RP remains the primary surgical objective. Clinical suspicion of incomplete excision of benign or cancer-containing prostate tissue may lead to removal of additional PPT samples. In this single-center study, prostate tissue was present in 45% of such samples overall, supporting this practice. However, cancer is rarely present in such samples (5.6% of cases with PPT removed, 1.5% of RP overall), with apical/urethral regions appearing to be at highest risk (~15% of samples).