Abstract 4814: Prediagnostic anthropometric measures and survival after diagnosis with colorectal cancer in the European Prospective Investigation into Cancer and Nutrition (EPIC).

Abstract

Abstract Background: Obesity is associated with increased colorectal cancer (CRC) risk, but very little research has been conducted to investigate the association between anthropometric factors and survival after CRC diagnosis. Methods: Therefore, we prospectively assessed the association between prediagnostic anthropometric measures [weight, height, body mass index (BMI), waist circumference (WC), hip circumference (HC), waist-to-hip ratio (WHR), waist-to-height ratio (WHtR)] with CRC-specific and overall mortality among 3,924 participants diagnosed with colorectal cancer (colon=2,462, rectum=1,462) between 1992 and 2008 in the EPIC cohort. Multivariable Cox proportional hazards models were used to calculate hazard ratios (HRs) and corresponding 95% confidence intervals (CIs) according to pre-defined categories and quintiles of anthropometric measures. Competing risk models were also utilized. Results: There were 1,309 deaths, 1,043 (80%) due to CRC. Mean follow-up after CRC diagnosis was 4 years. Being overweight (BMI=25-29.9 kg/m2) and obese (BMI≥30 kg/m2) was associated with increased CRC-specific mortality (HR=1.12, 95% CI, 0.97-1.30 and HR=1.26, 95% CI, 1.04-1.52, respectively; Ptrend=0.014) compared to normal weight patients (BMI<24.9 kg/m2). Comparable associations were observed for cancers in the colon (overweight, HR=1.06, 95%CI, 0.87-1.28; obese, HR=1.28, 95%CI, 1.00-1.63; Ptrend=0.066) and the rectum (overweight, HR=1.21, 95%CI, 0.93-1.56; obese, HR=1.35, 95%CI, 0.95-1.90; Ptrend=0.069). CRC patients with WHR in the highest quintile had an adjusted HR of 1.44, 95%CI, 1.09-1.90 (Ptrend =0.002) for CRC-specific mortality compared with the lowest quintile. Similar associations were seen for WC (HR=1.31, 95%CI: 1.00-1.71; Ptrend =0.011) and WHtR (HR=1.38, 95%CI: 1.05-1.82; Ptrend =0.006) for highest vs. lowest quintiles. The association with central obesity was stronger for rectal cancer (highest vs. lowest quintile, WHR: HR=2.42, 95%CI, 1.28-4.57; WC: HR=1.49, 95%CI, 0.89-2.48; WHtR: HR=2.19, 95%CI, 1.27-3.77) than for colon cancer (WHR: HR=1.16, 95%CI, 0.79-1.70; WC: HR=1.12, 95%CI, 0.78-1.60; WHtR: HR=1.17, 95%CI, 0.80-1.70). The associations with other anthropometric measures - height, weight, and HC, were not statistically significant. Subgroup analyses were conducted by sex, age at diagnosis, cancer stage and grade, location of tumor, time between blood collection and cancer diagnosis, year of diagnosis, follow-up period, diabetes status, and smoking status. Results for overall mortality were similar to those reported for CRC-specific mortality. Conclusions: Our preliminary results suggest that increased general obesity and central adiposity before diagnosis are associated with worse survival among Western European patients with CRC, but need to be confirmed in other studies. Citation Format: Veronika Fedirko, Elio Riboli, Tobias Pischon, Anne Tjønneland, H. Bas Bueno-de-Mesquita, Mazda Jenab, on behalf of the EPIC CRC Working Group. Prediagnostic anthropometric measures and survival after diagnosis with colorectal cancer in the European Prospective Investigation into Cancer and Nutrition (EPIC). [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 4814. doi:10.1158/1538-7445.AM2013-4814