Complete Intracorporeal Single-Stapling Technique Anastomosis Using a Novel Detachable Purse-String Instrument in Robotic Surgery With Transanal Total Mesorectal Excision for Low Rectal Cancer.

INTRODUCTION: New techniques for creating anastomoses have been evolving as colorectal surgery shifts toward more minimally invasive robotic platforms. However, robotic rectal cancer surgery still typically involves partial extracorporeal manipulation to secure the anastomotic anvil. We previously performed a simple robotic purse-string suture (RPSS) in complete intracorporeal double-stapling technique (DST) anastomosis and first reported its benefit in the surgical time and the burden on the assistant. Moreover, transanal total mesorectal excision (TaTME) for lower rectal cancer has attracted much attention due to emphasis on oncological safety and functional preservation. Even in TaTME, fixation of the anvil for single-stapling technique (SST) anastomosis is usually performed extracorporeally through the perineum, but in some cases, bulky tumor and/or narrow pelvis can make it difficult to get the specimen out of the perineum.

MATERIALS AND SURGICAL TECHNIQUE: We first introduce and report complete intracorporeal SST anastomosis in robotic low rectal cancer surgery with TaTME using a novel detachable purse-string instrument (PSI). The proximal mesentery is excised with a vessel sealer under pneumoperitoneum. Detachable PSI and anvil head are inserted into the body through the planned ileostomy site for SLAR with AV less than 5 cm. After fixation of the anvil to the proximal intestinal stump with the detachable PSI, the specimen is exteriorized from the same site. SST anastomosis with the rectal stump is performed using a Powered Stapler.

CONCLUSION: When it is difficult to remove the specimen from the perineum, this minimally invasive technique using a detachable PSI may be an option for SST anastomosis in robotic rectal cancer surgery with TaTME.