Complete Mesocolic Excision Appears Feasible in Right Colon Cancer

"In conclusion, data available from this interim analysis document that the quality of surgery measured by the length of the specimen, the area and integrity rate of the resected mesentery, and the length of [ileocolic and middle colic] vessels was higher in the CME arm, confirming that CME is an extended procedure compared with non-CME," according to the study authors.

Complete mesocolic excision (CME) demonstrated feasibility and safety in patients with right-sided colon cancer without increasing perioperative complications compared with conventional surgery, according to findings from the phase 3 CoME-In trial (NCT04871399) published in Annals of Surgical Oncology.

Investigators retrieved 25 lymph nodes in patients who underwent CME compared with 20 in those who did not receive CME (P = .012); the incidence of lymph node–positive disease was comparable between arms. Additionally, the rates of R0 resection in each respective arm were 99% vs 95%, and the median specimen lengths were 29 cm vs 28 cm. Patients typically had pathologic stage II disease (50%) followed by stage III disease (30%) and stage I tumors (19%).

In the CME and non-CME arms, respectively, the mean blood loss was 85 mL vs 100 mL (P = .7), and 3% and 3% of patients had intraoperative complications (P <.9). Additionally, 60% and 72% of patients in each arm had a postoperative stay of 5 or more days (P = .039).

Data highlighted postoperative complications in 26% of patients who received CME and 31% of those who did not undergo CME (P = .4). Moreover, moderate and severe complications occurred in 10.4% and 14.6% of patients from each respective group (P = .5), and 1 patient from each group died in the first month following surgery (P >.9).

“In conclusion, data available from this interim analysis document that the quality of surgery measured by the length of the specimen, the area and integrity rate of the resected mesentery, and the length of [ileocolic and middle colic] vessels was higher in the CME arm, confirming that CME is an extended procedure compared with non-CME,” the study authors wrote. “Hence CME is a safe and feasible technique, particularly when performed by experienced surgeons in referral centers.”

In this interventional, superiority trial, 251 patients were assigned to undergo surgical care with (n = 135) or without CME (n = 116). Surgeons conducted manual or mechanical anastomoses based on individual preference.

The trial’s primary end point was disease-free survival (DFS) at 3 years; data on this outcome were not available at the time of the study’s publication. Safety outcomes included duration of operation, intraoperative blood loss, intraoperative complications, postoperative complications, hospital length of stay, and postoperative mortality. Oncologic outcomes included the number of retrieved lymph nodes, number of positive lymph nodes collected, and overall survival.

Patients 18 to 85 years old with cT2-4aN0 or cT1-4aN–positive right-sided colon cancer were eligible for enrollment on the trial. Those who had distant metastases diagnosed during surgery or required unplanned multiorgan resection were ineligible for inclusion.

Among all patients included in the analysis, the median age was 74 years. Most patients had cecum tumors (40%), cT3 disease (62%), cN0 disease (58%), and cTNM stage III disease (39%).

Surgeons resected mesentery at a length of 106 cm² in the CME arm compared with 98 cm² in the non-CME group. The median length of ileocolic vessels was 13 cm and 12 cm in each respective group (P <.001), and the median length of middle colic vessels was 14 cm vs 12 cm (P = .017).

Investigators noted a significant relationship between the type of surgical approach and the occurrence of non-compliance in the CME arm (P = .041), as patients were more likely to not comply with open procedures than with minimally invasive strategies. Common surgical modalities included laparoscopic approaches (85%) followed by robotic approaches (7.6%), and open surgery (7.2%). Data showed no significant differences in the type of surgical procedure employed between the CME and non-CME arms (P = .057).

Reference

Degiuli M, Aguilar AHR, Solej M, et al. A randomized phase III trial of complete mesocolic excision compared with conventional surgery for right colon cancer: interim analysis of a nationwide multicenter study of the Italian Society of Surgical Oncology Colorectal Cancer Network (CoME-in trial). Ann Surg Oncol. 2024;31:1671-1680. doi:10.1245/s10434-023-14664-0