The impact of body mass index on oncological outcomes in colorectal cancer patients with curative intent

Background: Excess body weight is associated with a risk of several malignancies, including colon cancer. However, the oncological significance of evaluating body mass index (BMI) preoperatively in colorectal cancer (CRC) patients undergoing curative surgery has not been fully evaluated. Methods: Clinicopathological findings including BMI and laboratory data [carcinoembryonic antigen (CEA) and neutrophil/lymphocyte ratio (NLR)] from 358 curative CRC patients (open surgery group: n = 157; laparoscopic surgery group: n = 201) were assessed as indicators of survival outcome. BMI <20 was defined as underweight in both groups. Results: Not all categories of pathological findings were associated with BMI in both groups. Patients with BMI <20 showed significant poorer overall survival (OS) in the open surgery group. In addition, patients with BMI <20 in the laparoscopic surgery group were also significantly worse in OS and disease-free survival (DFS). Furthermore, multivariate analysis demonstrated that BMI was validated as independent predictors for OS and DFS in both groups. BMI had a significant negative correlation with NLR, which reflects host immune response in both groups. Conclusions: Lower BMI is a promising predictor of recurrence and prognosis in curative CRC patients.