Laparoscopic versus open resection for stage II/III rectal cancer in obese patients: A multicenter propensity score-based analysis of short- and long-term outcomes

Aim Whether a laparoscopic procedure can contribute to the improvement of clinical outcomes in obese patients with stage II/III rectal cancer compared to an open procedure remains unclear. Objective This study evaluated the technical and oncological safety of laparoscopic surgery versus open surgery in obese patients (body mass index [BMI] >= 25 kg/m(2)) with rectal cancer. Patients and Methods Data were collected from patients with pathological stage II/III rectal cancer and analyzed. Operations were performed via laparoscopic or open surgery from 2009 to 2013. A comparative analysis was performed after applying propensity score matching to the two cohorts (laparoscopic group and open group). The primary endpoint was 3-y relapse-free survival (RFS). Results Overall, 524 eligible cases were collected from 51 institutions. Equal numbers of propensity score-matched patients were included in the laparoscopic (n = 193) group and open (n = 193) group. Although the rate of D3 lymph node dissection did not differ between the laparoscopic group (87.0%) and the open group (88.6%), the median number of harvested lymph nodes was significantly lower in the laparoscopic group versus open group (17.5 vs 21, P = 0.0047). The median postoperative hospital stay was also significantly shorter in the laparoscopic group (14 d) vs the open group (17 d) (P = 0.0014). Three-y RFS was not significantly different between the two groups (hazard ratio 1.2454, 95% confidence interval 0.9201-1.6884, P = 0.4689). Conclusion The short- and long-term results of this large cohort study (UMIN ID: UMIN000033529) indicated that laparoscopic surgery in obese rectal cancer patients has advantageous short-term outcomes and no disadvantageous long-term outcomes.