title: Severe obesity prior to diagnosis limits survival in colorectal cancer patients evaluated at a large cancer centre.
abstract: BACKGROUND
  In contrast to the consistent evidence for obesity and colorectal cancer (CRC) risk, the impact of obesity in CRC patients is less clear. In a well-characterised cohort of CRC patients, we prospectively evaluated class I and class II obesity with survival outcomes.
  
  
  METHODS
  The CRC patients (N=634) were followed from the date of diagnosis until disease progression/first recurrence (progression-free survival (PFS)) or death (overall survival (OS)). Body mass index (BMI) was calculated from reported usual weight prior to diagnosis. Hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated in models adjusted for clinicopathologic, treatment, and lifestyle factors.
  
  
  RESULTS
  Over a median follow-up of 4 years, 208 (33%) patients died and 235 (37%) recurred or progressed. Class II obesity, as compared with either overweight or normal weight, was associated with an increased risk of death (HR and 95% CI: 1.55 (0.97-2.48) and 1.65 (1.02-2.68), respectively), but no clear association was observed with PFS. In analyses restricted to patients who presented as stages I-III, who reported stable weight, or who were aged <50 years, obesity was associated with a significant two- to five-fold increased risk of death.
  
  
  CONCLUSIONS
  In CRC patients evaluated at a large cancer centre, severely obese patients experienced worse survival outcomes independent of many other factors.
authors.affiliation: Department of Epidemiology, Division of OVP, Cancer Prevention and Population Sciences, The University of Texas MD Anderson Cancer Center, Unit 1340, 1515 Holcombe Boulevard, Houston, TX 77030, USA.
authors.forename: C R
authors.initials: CR
authors.lastname: Daniel
authors.affiliation: Department of Epidemiology, Division of OVP, Cancer Prevention and Population Sciences, The University of Texas MD Anderson Cancer Center, Unit 1340, 1515 Holcombe Boulevard, Houston, TX 77030, USA.
authors.forename: X
authors.initials: X
authors.lastname: Shu
authors.affiliation: Department of Epidemiology, Division of OVP, Cancer Prevention and Population Sciences, The University of Texas MD Anderson Cancer Center, Unit 1340, 1515 Holcombe Boulevard, Houston, TX 77030, USA.
authors.forename: Y
authors.initials: Y
authors.lastname: Ye
authors.affiliation: Department of Epidemiology, Division of OVP, Cancer Prevention and Population Sciences, The University of Texas MD Anderson Cancer Center, Unit 1340, 1515 Holcombe Boulevard, Houston, TX 77030, USA.
authors.forename: J
authors.initials: J
authors.lastname: Gu
authors.affiliation: Department of Gastroenterology, Hepatology, and Nutrition, Division of Internal Medicine, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.
authors.forename: G S
authors.initials: GS
authors.lastname: Raju
authors.affiliation: Department of Gastrointestinal Medical Oncology, Division of Cancer Medicine, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.
authors.forename: S
authors.initials: S
authors.lastname: Kopetz
authors.affiliation: Department of Epidemiology, Division of OVP, Cancer Prevention and Population Sciences, The University of Texas MD Anderson Cancer Center, Unit 1340, 1515 Holcombe Boulevard, Houston, TX 77030, USA.
authors.forename: X
authors.initials: X
authors.lastname: Wu
mesh_terms: D000328:Adult; D000368:Aged; D015992:Body Mass Index; D015179:Colorectal Neoplasms / Q000401:mortality*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D009765:Obesity / Q000150:complications*; D011446:Prospective Studies