BACKGROUND: Positive surgical margins (PSMs) in radical prostatectomy (RP) specimens are a frequent indication for adjuvant radiotherapy and are used as a measure of surgical quality.
However, the association between PSMs and prostate cancer-specific mortality (CSM) is poorly defined.
OBJECTIVE: Analyze the association of PSMs with CSM, adjusting for fixed and time-dependent parameters.
DESIGN, SETTING, AND PARTICIPANTS: Fine and Gray competing risk regression analysis was used to model the clinical data and follow-up information of 11 521 patients treated by RP between 1987 and 2005. Two extended models were used that adjusted for the use of postoperative radiotherapy, which was handled as a time-dependent covariate. Postoperative radiotherapy was modeled as a single parameter and also as early and late therapy, based on the prostate-specific antigen level at the start of treatment (≤ 0.5 vs >0.5 ng/ml).
INTERVENTION: RP for clinically localized prostate cancer and selective use of secondary local and/or systemic therapy.
OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: The outcome measure was prostate cancer-specific mortality.
RESULTS AND LIMITATIONS: The 15-yr CSM rates for patients with PSMs and negative surgical margins were 10% and 6%, respectively (p< 0.001). No significant association between PSM and CSM was observed in the conventional model with fixed covariates (hazard ratio [HR]: 1.04; 95% confidence interval [CI], 0.7-1.5; p=0.8) or in the two extended models that adjusted for postoperative radiotherapy (HR: 0.96; 95% CI, 0.7-1.4; p=0.9), or early and late postoperative radiotherapy (HR: 1.01; 95% CI, 0.7-1.4; p=0.9).
CONCLUSIONS: PSMs alone are not associated with a significantly increased risk of CSM within 15 yr of RP. However, urologists should continue to strive to avoid PSMs, as they increase a man's risk of biochemical recurrence and need for secondary therapy and may be a source of considerable patient anxiety.
Written by:
Stephenson AJ, Eggener SE, Hernandez AV, Klein EA, Kattan MW, Wood DP Jr, Rabah DM, Eastham JA, Scardino PT. Are you the author?
Glickman Urological and Kidney Institute, Cleveland Clinic, Cleveland, OH, USA.
Reference: Eur Urol. 2013 Aug 27. pii: S0302-2838(13)00864-6.
doi: 10.1016/j.eururo.2013.08.036
PubMed Abstract
PMID: 24035631
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