title: Reexamining the Association Between Positive Surgical Margins and Survival After Partial Nephrectomy in a Large American Cohort.
abstract: To investigate the impact of positive surgical margins (PSM) on overall survival (OS) in a large American cohort with intermediate-term follow-up.
  
  
  
  Using the National Cancer Data Base, we identified 6038 cases of pathological T1-T3a, nonmetastatic renal-cell carcinoma managed with partial nephrectomy (PN) from 2003 to 2006. Patients were stratified into two groups based on margin status. Predictors of positive margins were evaluated using multivariable logistic regression analysis. OS by margin status was evaluated using Kaplan-Meier analysis and the log-rank test. A multivariable Cox proportional hazards model was used to evaluate the adjusted association between margin status and survival.
  
  
  
  Overall, 302 (5.3%) patients had positive margins. On multivariable analysis, higher pathological T stage and higher comorbidity score were the only factors significantly associated with positive margins (p < 0.001 and p = 0.015, respectively). At 71-month median follow-up, the unadjusted 5-year OS for the entire cohort was 92%. Positive margins were significantly associated with decreased 5-year OS (89% vs 92%, p = 0.002), and this association remained significant in healthy patients (p = 0.027). On multivariable survival analysis, positive margins significantly predicted hastened time to all-cause death (hazards ratio 1.34; 95% CI 1.01, 1.78; p = 0.038).
  
  
  
  In the largest observational study to date, PSM were associated with worse OS after PN. Further study on cancer-specific outcomes with long-term follow-up is needed.
authors.affiliation: 1 Department of Urology, Glickman Urological and Kidney Institute, Cleveland Clinic , Cleveland, Ohio.
authors.forename: Matthew J
authors.initials: MJ
authors.lastname: Maurice
authors.affiliation: 1 Department of Urology, Glickman Urological and Kidney Institute, Cleveland Clinic , Cleveland, Ohio.|2 Division of Urology, Louis Stokes Cleveland Veterans Affairs Medical Center , Cleveland, Ohio.
authors.forename: Hui
authors.initials: H
authors.lastname: Zhu
authors.affiliation: 3 Urology Institute, University Hospitals Case Medical Center , Cleveland, Ohio.
authors.forename: Simon P
authors.initials: SP
authors.lastname: Kim
authors.affiliation: 3 Urology Institute, University Hospitals Case Medical Center , Cleveland, Ohio.
authors.forename: Robert
authors.initials: R
authors.lastname: Abouassaly
mesh_terms: D000368:Aged; D002292:Carcinoma, Renal Cell / Q000401:mortality / Q000601:surgery*; D015331:Cohort Studies; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D053208:Kaplan-Meier Estimate; D007680:Kidney Neoplasms / Q000401:mortality / Q000601:surgery*; D008297:Male; D000072662:Margins of Excision; D008875:Middle Aged; D009392:Nephrectomy / Q000379:methods*; D016016:Proportional Hazards Models; D016019:Survival Analysis; D013997:Time Factors; D016896:Treatment Outcome; D014481:United States