[Laparoscopic and robotic ultralow sphincter-saving operation and intersphincteric resection for rectal cancer:prevention and management for major complications].

In laparoscopic and robot-assisted ultra-low sphincter-saving surgeries for rectal cancer, preserving sexual function, preventing anastomotic leakage, anastomotic stricture, and low anterior resection syndrome (LARS) is critical to ensuring a good postoperative quality of life. The primary strategy for preventing postoperative sexual dysfunction is the meticulous preservation of the autonomic nerves, particularly the neurovascular bundles in the prostate area, guided by precise anatomical dissection. Partial preservation of the Denonvilliers fascia during total mesorectal excision (TME) not only helps protect the anterior mesorectum but also safeguards the neurovascular bundles. To prevent anastomotic leakage, it is essential to achieve clear oncologic margins, ensure a robust blood supply to both the proximal and distal margins, maintain a tension-free anastomosis, and avoid thermal or radiation injury whenever possible. In elderly patients with metabolic diseases, persistent descending mesocolon, or those undergoing neoadjuvant chemoradiotherapy, selective preservation of the left colic artery may be considered. Additionally, reinforcing the anastomosis with sutures at the 'dog-ear' site, closing the pelvic peritoneum, and placing a transanal tube for drainage are beneficial strategies. Early identification of anastomotic leakage and timely intervention to ensure drainage can prevent delayed leakage, strictures, and the structural sequelae of anastomotic failure. To minimize fecal dysfunction, selective exemption from radiotherapy may be beneficial for mid-to-high rectal cancer, while for low rectal cancer, reconstruction of J-pouch reservoirs, end-to-side anastomosis, and transverse coloplasty can help reduce the incidence of severe low anterior resection syndrome. Additionally, for low rectal cancer following neoadjuvant therapy, a selective rectum-preserving strategy that avoids major surgery can effectively prevent these complications.