LAUSR

Randomized controlled trials (RCTs) comparing intracorporeal anastomosis (IA) and extracorporeal anastomosis (EA) could not prove a significant reduction in postoperative stay and therefore did not provide sufficient evidence of IA. Recently, we reported a new intracorporeal anastomosis method and intracorporeal end-to-end anastomosis (IEEA). However, there have been no studies comparing intracorporeal side-to-side anastomosis (ISSA) to IEEA. The main purpose of this study is to verify the superiority of IA over EA. The secondary purpose is to compare IEEA with ISSA. Patients scheduled to undergo laparoscopic colectomy for colon cancer are recruited to the CONNECT study (multicenter, single-blind, randomized controlled study), cases in which anastomosis by the double-stapling technique is planned will be excluded. The target sample size is set at 300 cases in total, which will be randomized into 3 groups (EA, IEEA, and ISSA) in a 2:1:1 ratio. The primary endpoint is the length of postoperative hospital stay in the IA and EA groups; the secondly endpoint is the anastomotic time in IEEA and ISSA groups. We will also evaluate SF-36 ver.2, EORTC QLQ-C30 ver.3, operator stress using SURG-TLX, and the long-term outcomes, such as 5-year disease-free survival and overall survival. This RCT will compare the postoperative length of stay between IA and EA in twice the number of cases of previous RCTs. Concurrently, although as a secondary purpose, this will be the first study to compare IEEA and ISSA. Trial registration: This trial was registered with the UMIN Clinical Trials Registry in September 2020 as UMIN000041565.