title: Visceral obesity and colorectal cancer: are we missing the boat with BMI?
abstract: BACKGROUND
  Compared to subcutaneous fat, visceral fat is more metabolically active, leading to chronic inflammation and tumorigenesis. The aim of this study is to describe the effect of visceral obesity on colorectal cancer outcomes using computed tomography (CT) imaging to measure visceral fat.
  
  
  METHODS
  We conducted a retrospective chart review of patients who underwent surgical resection for colorectal cancer. Visceral fat volume was measured by preoperative CT scans. Final analysis was performed by stratifying patients based on oncologic stage.
  
  
  RESULTS
  Two hundred nineteen patients met the inclusion criteria, 111 viscerally obese and 108 nonobese. Body mass index (BMI) weakly correlated with visceral fat volume measurements (R                   (2) = 0.304). Whereas obese patients had no difference in survival when categorizing obesity by BMI, categorizing based on visceral fat volume resulted in significant differences in stage II and stage III patients. In stage II cancer, viscerally obese patients had a nearly threefold decrease in disease-free survival (hazard ratio (HR) = 2.72; 95 % confidence interval (CI) = 1.21, 6.10). In stage III cancer, viscerally obese patients had a longer time to recurrence (HR = 0.39; 95 % CI = 0.16, 0.99).
  
  
  CONCLUSIONS
  This study shows that viscerally obese patients with stage II colorectal cancer are at higher risk for poor outcomes and should be increasingly considered for adjuvant chemotherapy.
authors.affiliation: Division of Colorectal Surgery, Department of Surgery, Surgical Health Outcomes and Research Enterprise, University of Rochester Medical Center, 601 Elmwood Ave., Rochester, NY 14642, USA. aaron_rickles@urmc.rochester.edu
authors.forename: Aaron S
authors.initials: AS
authors.lastname: Rickles
authors.forename: James C
authors.initials: JC
authors.lastname: Iannuzzi
authors.forename: Oleg
authors.initials: O
authors.lastname: Mironov
authors.forename: Andrew-Paul
authors.initials: AP
authors.lastname: Deeb
authors.forename: Abhiram
authors.initials: A
authors.lastname: Sharma
authors.forename: Fergal J
authors.initials: FJ
authors.lastname: Fleming
authors.forename: John R T
authors.initials: JR
authors.lastname: Monson
mesh_terms: D000230:Adenocarcinoma / Q000150:complications / Q000401:mortality / Q000473:pathology / Q000601:surgery*; D000368:Aged; D015992:Body Mass Index; D003082:Colectomy; D015179:Colorectal Neoplasms / Q000150:complications / Q000401:mortality / Q000473:pathology / Q000601:surgery*; D005260:Female; D006801:Humans; D050152:Intra-Abdominal Fat / Q000000981:diagnostic imaging*; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D056128:Obesity, Abdominal / Q000150:complications* / Q000000981:diagnostic imaging; D011300:Preoperative Care; D012007:Rectum / Q000601:surgery*; D012189:Retrospective Studies; D016019:Survival Analysis; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome; D055105:Waist Circumference