Margin details matter: The prognostic significance of pseudocapsule invasion at the site of involved margin in prostatectomy specimens.

Abstract Background An involved surgical margin at prostatectomy has long been associated with elevated risk of prostate cancer recurrence; however, not all patients with an involved margin will relapse, and thus details of the involved margin may provide an opportunity for risk subset stratification. The present investigation seeks to determine whether a difference exists in recurrence rates when the margin involvement is at a site of prostate pseudocapsule invasion vs. within the prostate parenchyma proper. Methods Patients were retrospectively identified for inclusion by clinically localized disease and prostate-specific antigen (PSA) level of Results Between 2003 and 2010, 155 patients were identified for inclusion in the present study. The median age was 61 years, and all had clinical stage T1 and T2 disease (75% T1c). At diagnosis, the Gleason score was 6, 7, and 8–9 for 103 (66%), 42 (27%), and 10 (6%) patients, respectively, with median PSA level of 5.6 ng/ml (85%≤10). For 149 patients with reviewable margin site data, 51 (34%) demonstrated involvement within or beyond the pseudocapsule. At a median follow-up of 68 months (range: 13–137), 62 patients had experienced PSA relapse. The estimated 5-year PSA relapse rates for patients with an involved margin at the site of pseudocapsule invasion vs. prostate parenchyma were 49% vs. 34%, respectively ( P = 0.017; hazard ratio = 1.853). Conclusions Early PSA relapse rates are high for patients with involved surgical margin(s) without seminal vesicle or node involvement at prostatectomy; however, for patients who are followed without immediate adjuvant therapy, presence of tumor cells at the margin in a site of pseudocapsule invasion or penetration confers a higher risk of recurrence.