title: Robotic Rectal Cancer Resection: A Retrospective Multicenter Analysis.
abstract: BACKGROUND
  Conventional laparoscopy has been applied to colorectal resections for more than 2 decades. However, laparoscopic rectal resection is technically demanding, especially when performing a tumor-specific mesorectal excision in a difficult pelvis. Robotic surgery is uniquely designed to overcome most of these technical limitations. The aim of this study was to confirm the feasibility of robotic rectal cancer surgery in a large multicenter study.
  
  
  METHODS
  Retrospective data of 425 patients who underwent robotic tumor-specific mesorectal excision for rectal lesions at seven institutions were collected. Outcome data were analyzed for the overall cohort and were stratified according to obese versus non-obese and low versus ultra-low resection patients.
  
  
  RESULTS
  Mean age was 60.9 years, and 57.9 % of patients were male. Overall, 51.3 % of patients underwent neoadjuvant therapy, while operative time was 240 min, mean blood loss 119 ml, and intraoperative complication rate 4.5 %. Mean number of lymph nodes was 17.4, with a positive circumferential margin rate of 0.9 %. Conversion rate to open was 5.9 %, anastomotic leak rate was 8.7 %, with a mean length of stay of 5.7 days. Operative times were significantly longer and re-admission rate higher for the obese population, with all other parameters comparable. Ultra-low resections also had longer operative times.
  
  
  CONCLUSIONS
  Robotic-assisted minimally invasive surgery for the treatment of rectal cancer is safe and can be performed according to current oncologic principles. BMI seems to play a minor role in influencing outcomes. Thus, robotics might be an excellent treatment option for the challenging patient undergoing resection for rectal cancer.
authors.affiliation: Division of Surgical Oncology, Department of Surgery, Wright State University, Dayton, OH, USA, minia.hellan@wright.edu.
authors.forename: Minia
authors.initials: M
authors.lastname: Hellan
authors.forename: James
authors.initials: J
authors.lastname: Ouellette
authors.forename: Jorge A
authors.initials: JA
authors.lastname: Lagares-Garcia
authors.forename: Stephen M
authors.initials: SM
authors.lastname: Rauh
authors.forename: Harold L
authors.initials: HL
authors.lastname: Kennedy
authors.forename: John D
authors.initials: JD
authors.lastname: Nicholson
authors.forename: David
authors.initials: D
authors.lastname: Nesbitt
authors.forename: Craig S
authors.initials: CS
authors.lastname: Johnson
authors.forename: Alessio
authors.initials: A
authors.lastname: Pigazzi
mesh_terms: D000230:Adenocarcinoma / Q000473:pathology / Q000601:surgery*; D013505:Digestive System Surgical Procedures; D005240:Feasibility Studies; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D010535:Laparoscopy; D007902:Length of Stay; D008297:Male; D008875:Middle Aged; D019060:Minimally Invasive Surgical Procedures; D009367:Neoplasm Staging; D011183:Postoperative Complications; D011379:Prognosis; D012004:Rectal Neoplasms / Q000473:pathology / Q000601:surgery*; D012189:Retrospective Studies; D012307:Risk Factors; D065287:Robotic Surgical Procedures; D013997:Time Factors