Association between body mass index and prognosis of colorectal cancer

Abstract

Objective To explore the association between body mass index(BMI), clinicopathological characteristics, and prognosis of colorectal cancer patients. Methods Medical records and follow-up data of 107 patients with colorectal cancertreated in Chinese PLA General Hospital from July 2005 to June 2011 were analyzed retrospectively.The patients were divided into normal weight group(BMI<23.0kg/m2), overweight group(23.0 kg/m2≤BMI<27.5 kg/m2), and obese group(BMI≥27.5 kg/m2). The clinicopathological factors were compared among these three groups and the association between BMI and 5-year overall survival rate was analyzed. Results There were 37 patients(34.6%)in the normal weight group, 54 patients(50.5%)in the overweight group, and 16 patients(14.9%)in the obese group.The median survival time was 37 months.The 1-, 3-and 5-year overall survival rates were 95.3%, 81.9%, and 74.0%, respectively.According to the Kaplan-Meier method, tumor site, infiltrating degree, lymph metastasis, and clinical stage had significant effects on 5-year overall survival rate(P<0.05, respectively). BMI was significantly relevant to tumor infiltrating degree(P=0.039). No statistically significant correlation was found between BMI and 5-year overall survival rate, but the elevated BMI showed a trend toward increased 5-year overall survival rate(69.2% vs 72.0% vs 93.8%, P=0.239). Cox proportional hazards model indicated that the tumor site and clinical stage were significant independent risk factors(P<0.05, respectively), but BMI was not(P=0.343). Conclusions There is no significant association between BMI and prognosis of patients with colorectal cancer. Key words: Colorectal neoplasms; Body weight; Prognosis