Impact of body mass index on survival of esophageal squamous carcinoma patients in southern China.

Abstract

Although high body mass index (BMI) increases risk for developing esophageal adenocarcinoma (EAC), the prognostic influence of BMI is unknown in esophageal squamous carcinoma. BMI was calculated using measured height and weight at the first diagnosis and categorized as overweight (25 to 29.9 kg/m(2)), normal (18.5 to 24.9 kg/m(2)) or underweight (<18.5 kg/m(2)). Survival was compared by using the log-rank test on the Kaplan-Meier life table. Multivariate Cox regression analysis was used to evaluate whether BMI was an independent prognostic factor for disease-specific survival (DSS). Among 1,176 esophageal squamous carcinoma patients, 146 (12.4%) were categorized as overweight, and 277 (23.6%) underweight. More patients in the underweight group had anemia (P=0.001), weight loss (P=0.035) and R1 resection (P<0.001). Less patients in the underweight group received adjuvant chemotherapy (P=0.01). Patients in the overweight group had a higher incidence rate of high blood pressure (P<0.001), diabetes (P<0.001) and coronary artery diseases (P<0.001). Moreover, more patients in the overweight group had a lower TNM stage (P=0.003). In the univariated analysis, high BMI was significantly associated with better DSS (P=0.013). After adjusting for covariates enrolled for study, high BMI was an independent prognostic factor in weight loss esophageal squamous carcinoma patients.