Prostate cancer (PCa) patients found to have a positive surgical margin (PSM) in their radical prostatectomy specimen have a low long-term risk of systemic progression and cancer-related death, data show.
In a study of 2,895 PCa patients with a PSM, researchers at Mayo Clinic in Rochester, Minn., led by Stephen A. Boorjian, MD, found that the 15-year systemic- progression-free survival and cancer-specific survival was 90% and 93%, respectively, according to a report in Prostate Cancer and Prostatic Diseases (2012;15:56-62).
Greater tumor volume, higher pathological Gleason score, and advanced pathological tumor stage were associated with significantly increased risks of systemic progression and death from prostate cancer, but the number and location of positive margins were not.
In multivariate analysis, patients with pT3 or more advanced stage had a twofold increased risk of systemic progression and cancer-related death compared with patients who had pT2 stage cancer. Compared with patients with Gleason score 6, those with Gleason 7 or higher disease had a nearly fourfold increased risk of systemic progression and cancer-related death.
Receipt of adjuvant radiotherapy (RT) was associated with a 66% decreased likelihood of receiving salvage therapy or progression.
When the researchers excluded patients who received postoperative adjuvant RT from multivariate analysis, the variables of tumor volume, pathological tumor stage, and pathological Gleason score remained significantly associated with systemic progression and cancer-related death.
In their discussion of study limitations, the authors noted that the study was retrospective and nonrandomized. “As such, decisions to treat with adjuvant and salvage therapies were based on patient preference and physician counseling, and were thereby subject to inherent selection bias,” they wrote.
Following surgery, 439 patients (15%) received adjuvant RT, including 88 who were treated with concurrent adjuvant androgen deprivation therapy. The recipients of adjuvant RT had a significantly higher median preoperative PSA level and mean tumor volume than those who did not.