Tumor Gleason Grade and the Extent of Involvement at the Margin in Radical Prostatectomy Are Predictive of Prostate Cancer Recurrence
D Cao, AS Kibel, F Gao, PA Humphrey. Washington University School of Medicine, Saint Louis
Background: Radical prostatectomy (RP) is an effective method to treat prostate cancer. Many pathologic factors inlcuding positive margins have been identified as useful parameters to predict tumor recurrence. However, no study has assessed whether the tumor Gleason grade at the margin is predicitive of recurrence.
Design: 384 RPs (1989-2008) with at least one positive margin (bladder neck, distal apex, and peripheral), followup information, and available slides were retrieved. The following information was documented: age, tumor location (apex, base), Gleason grade of the main tumor and of the tumor at each positive margin, extraprostatic extension (focal, extensive), stage, positive margin location, and the extent of tumor involvement (ETI) at the margin (defined as tumor at the ink, measured with a micrometer as the aggregates in mm, bladder neck not measured). Prostate-specific antigen (PSA) recurence is defined as a serum PSA > 0.2 ng/ml after RP.
Results: The mean age of patients at the time of diagnosis were 61.2 years (38.8 to 80.3 years). The patients were followed for a mean of 46.1 months (range 0.7 to 232.4 months). There were total 446 positive margins in 384 cases: 327 cases with only 1 positive margin, 52 with 2 positive margins, and 5 with three positive margins. 56/384 (14.6%) had a positive bladder neck(BN), 154/384 (40.1%) had a positive distal apical margin, and 246/384 (64.15%) had a positive peripheral margin. The Gleason grade distribution of the main tumor and the tumor at the positive margins were in table 1 (13 cases were treated or margin significantly cauterized not listed).
|Gleason grade in main tumor||Highest Gleason grade at the margins|