Outcomes of robot-assisted versus laparoscopic surgery for colorectal cancer in morbidly obese patients: A propensity score-matched analysis of the US Nationwide Inpatient Sample.

BACKGROUND AND AIM: Morbid obesity is associated with poorer postoperative outcomes in colorectal cancer (CRC) patients. We aimed to evaluate short-term outcomes after robotic versus conventional laparoscopic CRC resection in morbidly obese patients.

METHODS: This population-based, retrospective study extracted data from the US Nationwide Inpatient Sample during 2005-2018. Adults ≥ 20 years old, with morbid obesity and CRC, and undergoing robotic or laparoscopic resections were identified. Propensity score matching (PSM) was applied to minimize the confounding. Univariate and multivariable regression was conducted to evaluate the associations between outcomes and study variables.

RESULTS: After PSM, 1296 patients remained. The risks of any postoperative complication (adjusted odds ratio [aOR] = 0.99, 95% confidence interval [CI]: 0.80, 1.22), prolonged length of stay (LOS) (aOR = 0.80, 95% CI: 0.63, 1.01), death (aOR = 0.57, 95% CI: 0.11, 3.10), or pneumonia (aOR = 1.13, 95% CI: 0.73, 1.77) were not significantly different between the two procedures after adjustment. Robotic surgery was significantly associated with greater hospital cost (aBeta = 26.26, 95% CI: 16.08, 36.45) than laparoscopic surgery. Stratified analyses revealed that, in patients with tumor located at the colon, robotic surgery was associated with lower risk of prolonged LOS (aOR = 0.72, 95% CI: 0.54, 0.95).

CONCLUSIONS: In patients with morbid obesity, risks of postoperative complication, death, or pneumonia are not significantly different between robotic and laparoscopic CRC resection. Among patients with tumor located at the colon, robotic surgery is associated with lower risk of prolonged LOS. These findings fill the knowledge gap and provide useful information for clinicians on risk stratification and treatment choice.