[Application of robotic surgical system in sphincter-preserving surgery for low rectal cancer].

Robotic surgical system has been widely applied in sphincter-preserving surgery for low rectal cancer with the advantages of clear 3D images and stably flexile manipulation. Its application principle includes radical resection of tumor and complete preservation of function. The main operation procedures of robotic surgical system in sphincter-preserving surgery for low rectal cancer are as follows: (1) Anterior resection of low rectal cancer: It is safe and feasible and has obvious advantages in observation of pelvic nerves, dissociation of presacral and sacral side, and high rate of sphincter-preserving, while the improvement of postoperative recovery and long-term survival needs to be verified by further large sample researches. (2) Per anus intersphincteric resection (ISR): It is mainly applied in T1 and T2 stage tumors with 2 cm distance from tumor low margin to anal edge after dissociation of mesorectum. The greater difficulty of manipulation is found in ISR, while robotic surgical system can complete the intersphincteric resection by transabdominal approach, but anal function may be affected with the possibility of feces spillage at night, so robotic ISR is now still in exploration stage. (3) Transanal everted pull-through resection (Welch resection): Associated application of this operation is rarely reported at home and abroad. Our department has completed 51 robotic procedures of Welch resection till March 2017. Welch resection is successfully performed in all the patients. The short-term clinical outcomes are quite satisfactory and long-term survival is followed up. We think that this procedure is safe and feasible under the strict mastering of indications. Owing to special manipulation advantages of quickly precise dissociation, cutting and anastomosis in small pelvic space, when compared to laparoscopic surgery, robotic surgical system has higher sphincter-preserving rate for low rectal cancer, however, no other advantages are found. We believe that with the development of surgical instruments and ongoing of large sample studies, robotic surgical system will play a more important role in the treatment of low rectal cancer.