ORLANDO—In men who have undergone radical prostatectomy (RP), positive surgical margins (PSM) for localized prostate cancer do not independently predict prostate cancer-specific mortality (PCSM), data show.
PSM is an independent predictor of post-RP biochemical recurrence and often is an indication for adjuvant therapy, but the association between PSM and PCSM has been poorly defined, investigators noted.
Andrew J. Stephenson, MD, of Cleveland Clinic in Ohio, and his colleagues studied 12,388 men who had RP for localized prostate cancer without prior therapy.
Of these, 2,712 (22%) had PSM, which was found in 1,337 (15%) of 8,679 patients with organ-confined disease and 1,375 (37%) of 3,709 with non-organ-confined cancer. In all, 848 men (7%) received postoperative radiation therapy. Over a median follow-up of 47 months, 180 patients died from prostate cancer and 662 died from competing causes, the investigators reported.
Of the patients who died from prostate cancer, 85 had PSM and 95 had negative margins. Although 15-year PCSM was significantly higher for patients with PSM than for those with negative margins (11% vs. 6%), PSM was not associated with PCSM after adjusting for standard clinical parameters, year of surgery, and postoperative radiotherapy.
The indiscriminate use of post-RP radiotherapy or systemic therapy “for patients with PSM in the absence of other adverse clinical features may do little to reduce mortality from prostate cancer,” Dr. Stephenson said.
Investigators reported study findings here at the 2009 Genitourinary Cancers Symposium.