Outcomes according to body mass index following laparoscopic surgery in patients with colorectal cancer.

PURPOSE

Body mass index (BMI) may not be appropriate for different populations. Therefore, the World Health Organization (WHO) suggested 25 kg/m as a measure of obesity for Asian populations. The purpose of this report was to compare the oncologic outcomes of laparoscopic colorectal resection with BMI classified from the WHO Asia-Pacific perspective.

PATIENTS AND METHODS

All patients underwent laparoscopic colorectal resection from September 2006 to March 2015 at a tertiary referral hospital. A total of 2408 patients were included and classified into four groups: underweight (n = 112, BMI <18.5 kg/m), normal (n = 886, 18.5-22.9 kg/m), pre-obese (n = 655, 23-24.9 kg/m) and obese (n = 755, >25 kg/m). Perioperative parameters and oncologic outcomes were analysed amongst groups.

RESULTS

Conversion rate was the highest in the underweight group (2.7%, P < 0.001), whereas the obese group had the fewest harvested lymph nodes (21.7, P < 0.001). Comparing oncologic outcomes except Stage IV, the underweight group was lowest for overall (P = 0.007) and cancer-specific survival (P = 0.002). The underweight group had the lowest proportion of national health insurance but the highest rate of medical care (P = 0.012).

CONCLUSION

The obese group had the fewest harvested lymph nodes, whereas the underweight group had the highest estimated blood loss, conversion rate to open approaches and the poorest overall and cancer-specific survivals.