Robotic versus laparoscopic intersphincteric resection for low rectal cancer: a systematic review and meta-analysis

Few studies have compared robotic and laparoscopic intersphincteric resection (ISR) in rectal cancer. Therefore, we performed a meta-analysis of recently published studies to compare perioperative outcomes of ISR for the treatment of low rectal cancer.We performed a systematic literature search of the Ovid-Medline, Ovid-EMBASE, and Cochrane Central Register of Controlled Trials databases for studies comparing robotic and laparoscopic ISR in patients with low rectal cancer. Demographic and clinical data were extracted from articles that met the inclusion and exclusion criteria. Perioperative outcomes of interest included the rate of diverting stoma, open conversion rate, operation time, estimated blood loss, length of hospital stay, time to first flatus, and time to initiate the postoperative diet. Oncological outcomes included the number of retrieved lymph nodes, distal resection margin, proximal resection margin, circumferential resection margin, 3-year overall survival, 3-year disease-free survival, and local recurrence. Postoperative complications included overall complications, a Dindo-Clavien classification ≥ III, and anastomotic leakage. All outcomes were compared between the two groups.We included 5 retrospective cohort studies with a total of 510 patients undergoing 273 (53.5%) robotic ISR procedures and 237 (46.5%) laparoscopic ISR procedures. The robotic ISR group lower conversion rate, lower blood loss, and longer operation times than the laparoscopic group. We also noted that fewer lymph nodes were harvested in the robotic ISR group; however, this difference was not statistically significant. Other outcomes were similar between the two groups.Robotic and laparoscopic ISR showed comparable perioperative outcomes, functional outcomes, and 3-year oncologic outcomes; however, robotic ISR was associated with a lower conversion rate and less blood loss despite longer operation times compared to laparoscopic ISR. These findings suggest that robotic ISR maybe a safe and effective technique for treating low rectal cancer in selected patients. The potential oncologic and functional benefits of robotic ISR should be evaluated in larger randomized controlled trials.