title: Variation in Surgical Margin Status by Surgical Approach among Patients Undergoing Partial Nephrectomy for Small Renal Masses.
abstract: OBJECTIVE
  We assessed the relationship of surgical margins across different surgical approaches to partial nephrectomy in patients with clinical T1a renal cell carcinoma in a population based cohort.
  
  
  METHODS
  We used NCDB (National Cancer Database) to identify all patients who underwent partial nephrectomy for clinical T1a renal cell carcinoma (tumor size less than 4 cm) from 2010 to 2011. The primary outcome was surgical margin status in patients treated with partial nephrectomy by the open, laparoscopic or robotic approach. Multivariable logistic regression analysis was done to identify patient, hospital and surgical factors associated with positive surgical margins.
  
  
  RESULTS
  Partial nephrectomy was done in 11,587 patients, including open, laparoscopic and robotic nephrectomy in 5,094 (44%), 1,681 (14%) and 4,812 (42%), respectively. Mean±SD age was 56±12 years. Overall 806 patients (7%) had positive surgical margins. The positive surgical margin prevalence was 4.9%, 8.1% and 8.7% for the open, laparoscopic and robotic approaches, respectively (p<0.001). Laparoscopic and robotic partial nephrectomy had a higher adjusted OR for positive surgical margins (OR 1.81 and 1.79, respectively, each p<0.001) than open nephrectomy. When stratified by hospital type, differences in positive surgical margin rates remained, such that patients treated at academic medical centers who underwent laparoscopic and robotic partial nephrectomy had a higher adjusted OR (1.38, p=0.074 and 1.73, p<0.001, respectively) than patients treated with open partial nephrectomy.
  
  
  CONCLUSIONS
  Laparoscopic and robotic partial nephrectomy is associated with higher positive surgical margin rates compared to open partial nephrectomy for clinical T1a renal cell carcinoma. The effect of margin status on long-term oncologic outcomes in this context remains to be determined.
authors.affiliation: Urology Institute, University Hospitals Case Medical Center, Case Western Reserve University, Cleveland, Ohio.
authors.forename: William
authors.initials: W
authors.lastname: Tabayoyong
authors.affiliation: Urology Institute, University Hospitals Case Medical Center, Case Western Reserve University, Cleveland, Ohio; Center for Health Care Quality and Outcomes, University Hospitals Case Medical Center, Case Western Reserve University, Cleveland, Ohio; Case Comprehensive Cancer Center, University Hospitals Seidman Cancer Center, Case Western Reserve University, Cleveland, Ohio.
authors.forename: Robert
authors.initials: R
authors.lastname: Abouassaly
authors.affiliation: Urology Institute, University Hospitals Case Medical Center, Case Western Reserve University, Cleveland, Ohio.
authors.forename: Jonathan E
authors.initials: JE
authors.lastname: Kiechle
authors.affiliation: Urology Institute, University Hospitals Case Medical Center, Case Western Reserve University, Cleveland, Ohio; Center for Health Care Quality and Outcomes, University Hospitals Case Medical Center, Case Western Reserve University, Cleveland, Ohio.
authors.forename: Edward E
authors.initials: EE
authors.lastname: Cherullo
authors.affiliation: Division of Hematology and Oncology, University Hospitals Case Medical Center, Case Western Reserve University, Cleveland, Ohio; Case Comprehensive Cancer Center, University Hospitals Seidman Cancer Center, Case Western Reserve University, Cleveland, Ohio.
authors.forename: Neal J
authors.initials: NJ
authors.lastname: Meropol
authors.affiliation: Division of Health Care Policy and Research, Mayo Clinic, Rochester, Minnesota.
authors.forename: Nilay D
authors.initials: ND
authors.lastname: Shah
authors.affiliation: Urology Institute, University Hospitals Case Medical Center, Case Western Reserve University, Cleveland, Ohio.
authors.forename: Shan
authors.initials: S
authors.lastname: Dong
authors.affiliation: Department of Urology, Mayo Clinic, Rochester, Minnesota.
authors.forename: R Houston
authors.initials: RH
authors.lastname: Thompson
authors.affiliation: Department of Surgical Oncology, Fox Chase Cancer Center, Philadelphia, Pennsylvania.
authors.forename: Marc C
authors.initials: MC
authors.lastname: Smaldone
authors.affiliation: Louis Stokes Cleveland Veterans Affairs Medical Center, Cleveland, Ohio; Department of Urology, Cleveland Clinic, Cleveland, Ohio.
authors.forename: Hui
authors.initials: H
authors.lastname: Zhu
authors.affiliation: Urology Institute, University Hospitals Case Medical Center, Case Western Reserve University, Cleveland, Ohio; Center for Health Care Quality and Outcomes, University Hospitals Case Medical Center, Case Western Reserve University, Cleveland, Ohio.
authors.forename: Sarah
authors.initials: S
authors.lastname: Ialacci
authors.affiliation: Urology Institute, University Hospitals Case Medical Center, Case Western Reserve University, Cleveland, Ohio; Center for Health Care Quality and Outcomes, University Hospitals Case Medical Center, Case Western Reserve University, Cleveland, Ohio; Case Comprehensive Cancer Center, University Hospitals Seidman Cancer Center, Case Western Reserve University, Cleveland, Ohio; Department of Internal Medicine, Cancer Outcomes and Public Policy Effectiveness Research Center, Yale University, New Haven, Connecticut. Electronic address: simkim@me.com.
authors.forename: Simon P
authors.initials: SP
authors.lastname: Kim
mesh_terms: D000328:Adult; D000368:Aged; D002292:Carcinoma, Renal Cell / Q000473:pathology* / Q000601:surgery*; D015331:Cohort Studies; D005260:Female; D006801:Humans; D007680:Kidney Neoplasms / Q000473:pathology* / Q000601:surgery*; D010535:Laparoscopy; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D018365:Neoplasm, Residual / Q000473:pathology* / Q000601:surgery*; D009392:Nephrectomy / Q000379:methods*; D065287:Robotic Surgical Procedures
keywords: carcinoma; kidney; minimally invasive surgical procedures; nephrectomy; outcome and process assessment (health care); renal cell