Splenic flexure cancer survival: a 25-year experience and implications for complete mesocolic excision (CME) and central vascular ligation (CVL).

BACKGROUND: The management of splenic flexure cancers (SFCs) in the era of complete mesocolic excision (CME) and central vascular ligation (CVL) is challenging because of its variable lymphatic drainage. This study aimed to compare survival outcomes for SFCs and non-SFCs, and better understand the clinicopathological characteristics which may define a distinct SFC phenotype. METHODS: An observational cohort study at Concord Hospital, Sydney was conducted with patients who underwent resection for colon adenocarcinoma (1995-2019). Clinicopathological data were extracted from a prospective database. Overall survival (OS) and disease-free survival (DFS) estimates and their associations to clinicopathological variables were investigated with Kaplan-Meier and Cox regression analyses. RESULTS: Of 2149 patients with colon cancer, 129 (6%) had an SFC. The overall 5-year OS and DFS rates were 63.6% (95% CI 62.5-64.7) and 59.4% (95% CI 58.3-60.5), respectively. SFCs were not associated with OS (P = 0.6) or DFS (P = 0.5). SFCs were more likely to present urgently (P < 0.001) with obstruction (P < 0.001) or perforation (P = 0.03), and more likely to require an open operation (P < 0.001). These characteristics were associated with poorer survival outcomes. No differences were noted between SFCs and non-SFCs with respect to tumour stage (P = 0.3). CONCLUSION: SFCs have a distinct phenotype, the individual characteristics of which are associated with poorer survival. However, the survivals of SFCs and non-SFCs are similar, possibly because the most important determinant of outcome, tumour stage, is no different between the groups. This may have implications for the surgical approach to SFCs with respect to standardization of CME and CVL surgery for these cancers.

Complete mesocolic excision in comparison with conventional surgery for right colon cancer: a nationwide multicenter study of the Italian Society of Surgical Oncology colorectal cancer network (CoME-in trial). Study protocol for a randomized controlled trial.

Complete mesocolic excision with central vascular ligation, or simply CME, includes the sharp dissection along the mesocolic visceral and parietal layers, with the ligation of the main vessels at their origins. To date, there is low evidence on its safety and efficacy. This is a study-protocol of a multicenter, randomized, superiority trial in patients with right-sided colon cancer. It aims to investigate whether the complete mesocolic excision improves the oncological outcomes as compared with conventional right hemicolectomy, without worsening early outcomes. Data on efficacy and safety of complete mesocolic excision are available only from a large trial recruiting eastern patients and from a low-volume single-center western study. No results on survival are still available. For this reason, complete mesocolic excision continues to be a controversial topic in daily practice, particularly in western world. This new nationwide multicenter large-volume trial aims to provide further data on western patients, concerning both postoperative and survival outcomes.

Complete Mesocolic Excision and Extent of Lymphadenectomy for the Treatment of Colon Cancer.

Curative-intent surgical resection of colon cancer involves optimal approaches to the peri-tumoral tissue, the mesocolon, and the draining lymph nodes. The key corresponding concepts that will be discussed are complete mesocolic excision (CME), central vascular ligation (CVL) or D3 dissection, and circumferential resection margin (CRM). We aim to describe these techniques and delineate evidence surrounding their technical feasibility, pathologic detail, as well as long-term oncologic impact. CME with CVL and D3 dissection are overlapping concepts both emphasizing anatomy-based resection of tumor and regional lymph nodes that does not breach the embryonic visceral fascia and ensures complete lymph node dissection up to the mesenteric root. Completeness of the mesocolic plane, number of harvested nodes, and CRM are surgical pathologic parameters that impact oncologic outcome. Attention to these details has been associated with improved outcomes in retrospective observational trials and the choice of open or minimally invasive approaches must be determined by surgeon's technical experiences.

Laparoscopic and open complete mesocolic excision with central vascular ligation for right colonic adenocarcinoma: a retrospective comparative study.

BACKGROUND: To examine the outcome of patients treated with complete mesocolic excision (CME) with central vascular ligation (CVL) after conventional and laparoscopic surgery. METHODS: We retrospectively evaluated stage I-IV colon adenocarcinoma patients treated by the same surgeon (L.M.) from 2013 to 2018. Postoperative complications, recurrences and survival are assessed. RESULTS: Fifty-one patients (M/F: 24/27) underwent laparoscopic right hemicolectomy with CME (L-CME) or open CME (O-CME) plus CVL. Tumour location was the caecum in 39.2% of cases, the transverse in 23.5%, the hepatic colonic flexure in 21.5%, and the ascending colon in 15.6%. Twenty-four patients underwent L-CME while 27 underwent O-CME. More than 15 harvested lymphnodes are reported in 74.1% of O-CME patients and in 66.7% of L-CME patients (p = 0.562). Postoperative complications occurred in 7 O-CME and 5 L-CME patients, respectively (p = 0.669). Three-year overall survival, including stage IV, was of 75% versus 77.8% for L-CME and O-CME patients, respectively, while for stage I-III, was of 88.9% vs. 80% in L-CME and O-CME, respectively (p = 0.440). The median follow-up was of 2.43 years. CONCLUSION: CME with CVL is a meticulous, complex but feasible technique. In our experience, oncological results in terms of recurrences and overall survival, after conventional and laparoscopic CME plus CVL, are comparable. Patients with stage I-III colon adenocarcinoma have a better prognostic trend especially when more than 15 lymphnodes are removed. The respect of oncological radicality and the correct indication to minimally invasive surgery are the undiscussed key outcome variables.

[Intraoperative anatomical observation of mesentery morphology of colonic splenic flexure].

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.

Selective central vascular ligation (D3 lymphadenectomy) in patients undergoing minimally invasive complete mesocolic excision for colon cancer: optimizing the risk-benefit equation.

AIM: Complete mesocolic excision (CME) with central vascular ligation (CVL) has been advocated for right colon adenocarcinoma (RC), but the radicality of vascular dissection remains controversial. Our aim is to report outcomes of selective CVL (D3 lymphadenectomy) during minimally invasive CME for RC. METHOD: A prospective database identified patients who were treated for RC between 2009 and 2016. Minimally invasive CME was standard. The radicality of lymphadenectomy was defined as high ligation (HL) versus CVL based on operative reports and videos. Two blinded radiologists independently evaluated the pre- and postoperative CT scans for radiographically abnormal nodes. RESULTS: Of 197 patients who underwent CME, HL was performed in 56 (28%) and CVL in 141 (72%). There were no baseline differences in age, sex, body mass index, American Society of Anesthesiologists score or pathological staging, and there were no major intra-operative complications in either group (including no major vascular injuries). The median total number of nodes retrieved was 27 and 31 (P = 0.011) in HL and CVL groups, resepctively, with pathologically positive nodes identified in 33.9% and 39.8% (P = 0.704), respectively. Preoperative imaging identified abnormal cN3 nodes in 1.5% of patients; all of whom underwent CVL. No abnormal cN2 or cN3 nodes remained on postoperative imaging. The 60-day mortality was 0.5%, and major morbidity was 4%. One patient (0.5%) had an anastomotic recurrence after a median follow-up of 22 months. CONCLUSION: With imperfect preoperative clinical nodal staging, and in the absence of randomized data, the low morbidity and oncological outcomes observed support the approach of CME with HL as a minimum standard, with CVL (D3 lymphadenectomy) in selected cases.

Laparoscopic surgery for colorectal cancer with persistent descending mesocolon.

BACKGROUND: Persistent descending mesocolon (PDM) is caused by the absence of fusion of the descending colon to the retroperitoneum. We herein report two colorectal cancer cases with PDM that were treated with laparoscopic surgery. CASE PRESENTATION: Case 1: a 50-year-old man with sigmoid colon cancer and synchronous liver metastasis. After neoadjuvant chemotherapy, he underwent laparoscopic sigmoidectomy with lymph node dissection cutting the root of the inferior mesenteric artery (IMA) and synchronous liver resection. He experienced postoperative stenosis of the reconstructed colon possibly due to an impaired arterial blood flow in the reconstructed colon. Case 2: a 77-year-old man with rectal cancer. Laparoscopic low anterior resection preserving the left colic artery (LCA) was performed. Intraoperative infrared ray (IR) imaging using indocyanine green (ICG) showed good blood flow of the reconstructed colon. He had no postoperative complications. In cases of PDM, the mesentery of the descending and sigmoid colon containing the LCA is often shortened, and the marginal artery of the reconstructed colon is located close to the root of the LCA. Lymph node dissection accompanied by cutting the LCA carries a risk of marginal artery injury. Therefore, we recommend lymph node dissection preserving the LCA in colorectal cancer patients with PDM in order to maintain the blood flow of the reconstructed colon. If the IMA and LCA absolutely need to be cut for complete lymph node dissection, the marginal artery should be clearly identified and preserved. In addition, intraoperative IR imaging is extremely useful for evaluating colonic perfusion and reducing the risk of anastomotic complications. CONCLUSION: In colorectal cancer surgery in patients with PDM, surgeons should be aware of these tips for maintaining the blood flow of the reconstructed colon and thereby avoid postoperative complications caused by an impaired blood flow.

Is hook diathermy safe to dissect the mesoappendix in paediatric patients? A 10-year experience.

BACKGROUND: Laparoscopic appendicectomy is one of the most commonly performed abdominal surgical procedures in children, with many different techniques used to isolate and control the appendiceal artery. Previous studies have looked into the utility of different methods of mesoappendix dissection, however these have been predominantly small-scale studies performed on adults. AIM: The current study aimed to assess the safety and efficacy of 'hook' diathermy as a sole means of mesoappendix dissection in children under 15 years of age undergoing laparoscopic appendicectomy. METHODS: Retrospective review of hospital database and electronic clinical notes of children aged under 15 who underwent laparoscopic appendicectomy at Starship Children's Hospital between 1 January 2007-31 December 2016. RESULTS: During the study period, 2,793 children had appendicectomy using hook diathermy to dissect the mesoappendix. No children required blood transfusions or return to theatre for bleeding. There were 103 intra-operative complications related to the use of hook diathermy (3.7%), including one case that required conversion to open for bleeding. CONCLUSION: Dissection of the mesoappendix using hook diathermy is a safe, quick and effective method during laparoscopic appendicectomy, with low complication and conversion to open rates.

Complete mesocolic excision and central vascular ligation for right colon cancer: an introduction for abdominal radiologists.

OBJECTIVE: To provide an overview of complete mesocolic excision, along with a review of the relevant vascular anatomy and locoregional staging concepts, for abdominal radiologists. RESULTS: Complete mesocolic excision (CME) with central vascular ligation (CVL) for colon cancer has emerged as a technique that has growing interest in surgical oncology. Specific anatomic considerations and patterns of nodal spread have thus gained clinical significance, and should be familiar to abdominal radiologists. This review article provides an overview of CME with CVL, and discusses some of the important anatomic considerations in patients with colon cancer that are relevant to radiologists. CONCLUSION: Knowledge of CME with CVL and the relevant anatomic and staging considerations is important for abdominal radiologists, as this surgical technique becomes increasingly utilized.

How to do a laparoscopic high left colectomy with complete mesocolic excision and central vascular ligation for splenic flexure cancer.

Due to a lack of a standardized surgical approach in splenic flexure cancer, we consider useful to present a how to do it material on laparoscopic high left colectomy with complete mesocolic excision and central vascular ligation for this type of tumours.