Short- and long-term impact of body mass index on laparoscopic rectal cancer surgery

Aim Obesity is associated with increased technical difficulty in laparoscopic surgery. However, its impact has been measured mainly for colectomy but not specifically for rectal excision. The aim of the study was to assess the impact of body mass index (BMI) on technical feasibility and oncological outcome of laparoscopic rectal excision for cancer. Method A total of 490 patients treated by laparoscopic rectal excision for rectal cancer from January 1999 to June 2010 were included. Seventy per cent had had preoperative radiochemotherapy. Patients were separated into four groups according to BMI (kg/m2): <20, 2025, 2530 and 30. The impact of BMI on conversion, surgical morbidity, quality of excision (Quirke mesorectal grade and circumferential resection margin) and long-term oncological outcome was determined. Results Among the 490 patients BMI was <20 in 43, 2025 in 223, 2530 in 177 and 30 in 47. Mortality (overall 1%) and morbidity (overall 19%) were similar between the groups. Conversion in the four groups was 5%, 14%, 23% and 32% (P=0.001). The quality of mesorectal excision and circumferential margins did not differ between the groups. The 5-year local recurrence rates (0%, 4.6%, 5.3% and 5.9% respectively; P=0.823) and the overall and disease-free survival were not significantly influenced by BMI. Conclusion In laparoscopic surgery for rectal cancer, BMI influenced the risk of conversion but not surgical morbidity, quality of surgery and survival. This suggests that all patients, including obese patients, are suitable for laparoscopic surgery.