Intraoperative anatomical observation of mesentery morphology of colonic splenic flexure / 中华胃肠外科杂志

Objective: At present, surgeons do not know enough about the mesenteric morphology of the colonic splenic flexure, resulting in many problems in the complete mesenteric resection of cancer around the splenic flexure. In this study, the morphology of the mesentery during the mobilization of the colonic splenic flexure was continuously observed in vivo, and from the embryological point of view, the unique mesenteric morphology of the colonic splenic flexure was reconstructed in three dimensions to help surgeons further understand the mesangial structure of the region. Methods: A total of 9 patients with left colon cancer who underwent laparoscopic radical resection with splenic flexure mobilization by the same group of surgeons in Union Hospital of Fujian Medical University from January 2018 to June 2019 were enrolled. The splenic flexure was mobilized using a "three-way approach" strategy based on a middle-lateral approach. During the process of splenic flexure mobilization, the morphology of the transverse mesocolon and descending mesocolon were observed and reconstructed from the embryological point of view. The lower margin of the pancreas was set as the axis, and 4 pictures for each patient (section 1-section 4) were taken during middle-lateral mobilization. Results: The median operation time of the splenic flexure mobilization procedure was 31 (12-55) minutes, and the median bleeding volume was 5 (2-30) ml. One patient suffered from lower splenic vessel injury during the operation and the bleeding was stopped successfully after hemostasis with an ultrasound scalpel. The transverse mesocolon root was observed in all 9 (100%) patients, locating under pancreas, whose inner side was more obvious and tough, and the structure gradually disappeared in the tail of the pancreatic body, replaced by smooth inter-transitional mesocolon and dorsal lobes of the descending colon. The mesenteric morphology of the splenic flexure was reconstructed by intraoperative observation. The transverse mesocolon was continuous with a fan-shaped descending mesocolon. During the embryonic stage, the medial part (section 1-section 2) of the transverse mesocolon and the descending mesocolon were pulled and folded by the superior mesenteric artery (SMA). Then, the transverse mesocolon root was formed by compression of the pancreas on the folding area of the transverse mesocolon and the descending mesocolon. The lateral side of the transverse mesocolon root (section 3-section 4) was distant from the mechanical traction of the SMA, and the corresponding folding area was not compressed by the tail of the pancreas. The posterior mesangial lobe of the transverse mesocolon and the descending mesocolon were continuous with each other, forming a smooth lobe. This smooth lobe laid flat on the corresponding membrane bed composed of the tail of pancreas, Gerota's fascia and inferior pole of the spleen. Conclusions: From an embryological point of view, this study reconstructs the mesenteric morphology of the splenic flexure and proposes a transverse mesocolon root structure that can be observed consistently intraopertively. Cutting the transverse mesocolon root at the level of Gerota's fascia can ensure the complete resection of the mesentery of the transverse colon.

Laparoscopic Surgery for Splenic Flexure Colon Cancer

Purpose: While a carcinoma of the splenic flexure is uncommon, is associated with a high risk of obstruction, and has a dual lymphatic drainage system, A COST study excluded transverse colon cancer, including splenic flexure colon cancer. This study reviews our experience with splenic flexure colon cancer treated laparoscopically and discusses a appropriate, safe laparoscopic surgical procedure. Methods: The authors reviewed the medical records of patients who underwent laparoscopic surgery for splenic flexure colon cancer from January 1995 to June 2006. The splenic flexure colon was defined as 5 cm from the splenic flexure proximally and distally by using radiologic studies. Curative surgery for splenic flexure colon cancer was defined as: primary cancer removal, a safe resected margin, no metastasis, and a complete lymphadenectomy including high ligation of left colic artery and of the left branch of the middle colic artery. Results: A total of 407 patients underwent laparoscopic surgery for colon cancer; among them, 15 patients underwent a laparoscopic left colectomy for splenic flexure colon cancer. The mean age of the patients was 63.8 years, and the male-to-female ratio was 9:6. The mean operation time was 325.3+/-95.1 minutes, and the average hospital stay was 15.8+/-4.9 days. The average number of harvested lymph nodes was 12.3+/-9.7, the average distal resection margin was 15.3+/-7.6 cm, and the average proximal margin was 10.7+/-3.2 cm. One case of chyle discharge and one case of ileus developed, but were treated conservatively. There was no surgical mortality. Conclusions: A laparoscopic left colectomy for splenic flexure colon cancer is a technically feasible and safe procedure with acceptable short-term outcomes in experienced hands.