Short- and long-term outcomes of minimally invasive total mesorectal excision in obese versus nonobese patients with rectal cancer: a propensity score matched study

Abstract Background Obesity adds technical complexity to colorectal surgery and has been linked to higher rates of perioperative complications and poorer long-term outcomes. Its prevalence is increasing among patients undergoing minimally invasive total mesorectal excision for rectal cancer; however, its impact on perioperative and oncologic outcomes remains controversial. Therefore, the aim of this study was to compare short- and long-term outcomes between obese (body mass index (BMI) ≥ 27 kg/m 2 ) and nonobese patients undergoing minimally invasive total mesorectal excision. Methods Retrospective review of patients with rectal cancer undergoing laparoscopic, robotic, or transanal total mesorectal excision (TME) between January 2015 and December 2022. Propensity score matching (1:1) was performed on baseline characteristics. Primary outcomes included perioperative parameters, postoperative complications, and long-term oncologic outcomes. Results After matching, 142 patients were included in each group. Obesity was associated with higher conversion rates to open surgery (2.8% versus 0%, p = 0.044) and increased overall complications (40.1% versus 28.9%, p = 0.046), driven mainly by surgical wound infections (9.2% versus 1.4%, p = 0.004). No differences were observed in major complications, anastomotic leakage, hospital stay, margin status, or 5-year overall (88% versus 89.4%, p = 0.409) and disease-free (62.7% versus 72.5%, p = 0.653) survival. Conclusions Obesity increased conversion and minor complication rates but did not adversely affect short-term outcomes or long-term oncologic outcomes after minimally invasive TME procedures. Tailored perioperative strategies may mitigate obesity-associated risks. Trial registration Not applicable.