Visceral obesity, body mass index and risk of complications after colon cancer resection: A retrospective cohort study.

Background: The aim of our study was to assess the influence of visceral obesity (VO), as measured by preoperative abdominal CT scan, in relation to body mass index (BMI) on the incidence of postoperative complications and duration of hospital stay after colon cancer surgery.

Methods: Patients who underwent elective resection for colon cancer between January 1, 2006, and December 31, 2013, and had a preoperative CT scan were entered in the study. Visceral fat area (VFA) was determined by using the preoperative CT scan at the L3-L4 level. The effect of VO, defined as a VFA of >100 cm², on postoperative complications and duration of hospital stay was analyzed.

Results: Of 564 included patients, 65% had VO. VO was associated with more anastomotic leakage (P = .04), pneumonia (P = .02), wound infection (P = .03), reoperations (P = .04), and longer duration of hospital stay (P = .05). Of patients with a BMI < 25 kg/m², 44% had VO. In this group, VO was associated significantly with postoperative complications, cardiac (P < .01) and pulmonary (P = .01) comorbidity, hypertension (P < .01), and diabetes (P < .01). In the overweight (BMI 25-30 kg/m²) and obese (BMI > 30 kg/m²) groups, the rate of VO was much higher (81% and 90%, respectively), but was not associated significantly with complications or comorbidity, except for cardiac comorbidity (P < .02) in the BMI = 25-30 kg/m² group. After multivariable analysis, VO was shown to be an independent predictor of anastomotic leakage and wound infection.

Conclusion: The association of VO with worse outcome after colon cancer surgery is most pronounced in patients with a BMI < 25 kg/m².