The Radical Extent of lymphadenectomy - D2 dissection versus complete mesocolic excision of LAparoscopic Right Colectomy for right-sided colon cancer (RELARC) trial: study protocol for a randomized controlled trial

The effect of ileal resection length on postoperative complications and prognosis in right colon cancer

BACKGROUND

There is a lack of literature on the length of the terminal ileum to be resected in right hemicolectomy for colon cancer. Therefore, we aimed to determine the mean ileal loop length and the effect of this variation on postoperative complications and long-term oncological outcomes in patients who underwent right hemicolectomy.

METHODS

Right hemicolectomy surgeries performed for colon cancer in a tertiary care hospital between January 2011 and December 2018 were retrospectively analyzed from a prospective database. Two patient groups were established based on the mean length of the resected ileum above and below 7 cm. The two groups were compared for clinicopathological data, postoperative complications, mortality, long-term overall survival (OS) and disease-free survival (DFS). The factors contributing to OS and DFS were analyzed.

RESULTS

The study included 217 patients. Body mass index (BMI) values were significantly higher in the ileum resection length > 7 cm group (p = 0.009). Pathological N stage, tumor diameter, and number of metastatic lymph nodes were significantly higher in the ileum resection length > 7 cm group (p = 0.001, p = 0.001, and p = 0.026, respectively). There was no significant difference for postoperative complication and mortality rates between the two groups. The mean follow-up period was 61.2 months (2-120) in all patients. The total number of deaths was 29 (11.7%) while the 60-month OS was 83.5% and 50-month DFS was 81.8%. There was no significant difference between the groups in terms of OS and DFS rates (p > 0.05).

CONCLUSIONS

Excessive resection of the distal ileum in right hemicolectomy does not provide any benefit in terms of prognosis and complications.The ileum resection length and values close to it in our study appear to be sufficient.

Comparison of D2 vs D3 lymph node dissection for RIght COloN cancer (RICON): study protocol for an international multicenter open-label randomized controlled trial

BACKGROUND

Colon cancer is a global health concern, ranking fifth in both new diagnoses and deaths among tumors worldwide. Surgical intervention remains the primary treatment for localized cases, with a historical evolution marked by a focus on short-term outcomes. While Japan pioneered radical tumor removal with a systematic categorization of lymph nodes (D1, D2, D3), the dissemination of Japanese practices to the West was delayed until 90th of last century. Discrepancies between Japanese D3 dissection and the CME with CVL principle persist, with variations in longitudinal margins and recommended procedures. Non-randomized trials indicate the superiority of D3 over D2, but a consensus is lacking.

METHODS

This prospective, international, multicenter, randomized controlled trial employs a two-arm, parallel-group, open-label design to rigorously compare the 5-year overall survival outcomes between D2 and D3 lymph node dissection in stage II-III right colon cancer. Building on prior studies, the trial aims to address existing knowledge gaps and provide a comprehensive evaluation of the outcomes associated with D3 dissection. The study population comprises patients with right colon cancer, ensuring a focused investigation into the specific context of this disease. The trial design emphasizes its global scope and collaboration across multiple centers, enhancing the generalizability of the findings.

DISCUSSION

This study's primary objective is to elucidate the potential superiority in 5-year overall survival benefits of D3 lymph node dissection compared to the conventional D2 approach in patients with stage II-III right colon cancer. By examining this specific subset of patients, the research aims to contribute valuable insights into optimizing surgical strategies for improved long-term outcomes. The trial's international and multicenter nature enhances its applicability across diverse populations. The outcomes of this study may inform future guidelines and contribute to the ongoing discourse surrounding the standardization of colon cancer surgery, particularly in the context of right colon cancer.

TRIAL REGISTRATION

ClinicalTrials.gov NCT03200834. Registered on June 27, 2017.

Robotic approach to colonic resection: For some or for all patients?

The robotic approach is rapidly gaining momentum in colorectal surgery. Its benefits in pelvic surgery have been extensively discussed and are well established amongst those who perform minimally invasive surgery. However, the same cannot be said for the robotic approach for colonic resection, where its role is still debated. Here we aim to provide an extensive debate between selective and absolute use of the robotic approach for colonic resection by combining the thoughts of experts in the field of robotic and minimally invasive colorectal surgery, dissecting all key aspects for a critical view on this exciting new paradigm in colorectal surgery.

Natural orifice specimen extraction surgery versus small-incision assisted laparoscopic radical right hemicolectomy

Conventional laparoscopic-assisted right hemicolectomy requires a small abdominal incision to extract the specimen, which becomes an important source of postoperative complications and impairs perioperative experience. Transvaginal natural orifice specimen extraction surgery (NOSES VIIIA) avoids this small incision by extracting the specimen through the vagina. Here we describe the design of a multicenter, open-label, parallel, noninferior, phase III randomized controlled trial (NCT05495048). The aim of this study is to confirm that the NOSES VIIIA procedure is not inferior to small-incision assisted right hemicolectomy in long-term oncological efficacy. A total of 352 female patients with right colon adenocarcinoma/high-grade intraepithelial neoplasia will be randomly assigned to the NOSES VIIIA arm and the small-incision arm in a 1:1 ratio. The primary end point of this trial is 3 year disease-free survival. Clinical Trial Registration: NCT05495048 (ClinicalTrials.gov).

Macroscopic Evaluation of Colon Cancer Resection Specimens

Colon cancer is a common disease internationally. Outcomes have not improved to the same degree as in rectal cancer, where the focus on total mesorectal excision and pathological feedback has significantly contributed to improved survival and reduced local recurrence. Colon cancer surgery shows significant variation around the world, with differences in mesocolic integrity, height of the vascular ligation and length of the bowel resected. This leads to variation in well-recognised quality measures like lymph node yield. Pathologists are able to assess all of these variables and are ideally placed to provide feedback to surgeons and the wider multidisciplinary team to improve surgical quality over time. With a move towards complete mesocolic excision with central vascular ligation to remove the primary tumour and all mechanisms of spread within an intact package, pathological feedback will be central to improving outcomes for patients with operable colon cancer. This review focusses on the key quality measures and the evidence that underpins them.

Bach Mai Procedure for complete mesocolic excision, central vascular ligation, and D3 lymphadenectomy in total laparoscopic right hemicolectomy: a prospective study

PURPOSE

Total laparoscopic right hemicolectomy with complete mesocolic excision (CME), central vascular ligation (CVL), and D3 lymphadenectomy is still the most challenging colon procedures for gastrointestinal surgeons. We herein report the technical details and our preliminary experience of Bach Mai Procedure - a novel-combining (cranial, medial to lateral, and caudal) approach with early resection of the terminal ileum.

METHODS

The dissection stage was central vascular isolation and ligation by a combined multiple approaches in the following four steps: cranial approach, dissecting along the inferior aspect of pancreatic isthmus to reveal the middle colic vessels and the anterior aspect of the superior mesentery vein and then exposed the right gastroepiploic vein and the trunk of Henle; medial-to-lateral approach, exposing the surgical axis - the superior mesenteric vascular axis and then early resection of the terminal ileum to open the dissection from the bottom up; and caudal approach, radical ligation of the ileocecal artery and right colic artery (central vascular ligation), lymph node dissection (D3 lymphadenectomy), and resecting the Toldt fascia of the colon to release the entire right colon from the abdominal wall.

RESULTS

In 12 months, there were 32 cases of primary right-sided colon malignancies that have undergone tLRH_{D3, CME/CVL} based on the Bach Mai Procedure. In 3 cases (9.4%), the tumor site was hepatic flexure. The median of lymph node number (LNN) was 38, with the maximum number which was 101. No serious postoperative complications (grade 3 or higher) neither inhospital mortality was detected.

CONCLUSION

This Bach Mai procedure, a novel-combining approach with early resection of the terminal ileum, is technically feasible and safe for tLRH_{D3, CME/CVL}. Further investigations and follow-up must be proceeded to evaluate the long-term outcomes of our technique.

Intracorporeal Anastomosis Versus Extracorporeal Anastomosis in Laparoscopic Right Colectomy: An Observational Cohort Study

BACKGROUND

Current studies did not draw definitive conclusions on comparison of intracorporeal anastomosis (ICA) with extracorporeal anastomosis (ECA) in laparoscopic right colectomy. Whether the intraperitoneal contamination induced by ICA can result in higher risk of postoperative abdominal infection remains unclear. This study was aimed to compare the short-term outcomes, especially the risk of abdominal infection after ICA versus ECA.

METHODS

This was an observational cohort study as a secondary analysis of a randomized controlled trial (RCT)-RELARC trial (NCT02619942). The patients enrolled in the RELARC trial were diagnosed with primary colon adenocarcinoma without distant metastasis and underwent radical laparoscopic right colectomy between Jan 2016 and Dec 2019. In our study the patients who converted to open surgery in RELARC trial were excluded. The short-term outcomes were compared between ICA and ECA. The primary endpoint was abdominal infection. The inverse probability of treatment weighting (IPTW) and propensity score matching (PSM) was used for adjusting the potential confounders.

RESULTS

This study enrolled 975 patients with 119 patients undergoing ICA and 856 patients undergoing ECA. The incidence of abdominal infection was higher in ICA group (9.2% versus 1.5%, RR from IPTW = 5.7 (95%CI: 2.6-12.6), P < 0.001) as well as the incidence of wound infection (14.3% vs 3.3%, RR from IPTW = 5.0 (95%CI: 2.9-8.6), P < 0.001). ICA was associated with higher incidence of Clavien-Dindo (CD) grade I and II complications (CD-I: 15.1% versus 6.8%, RR from IPTW = 2.4 (95%CI: 1.5-3.9), P < 0.001; CD-II: 26.9% versus 8.2%, RR from IPTW = 3.6 (95%CI: 2.5-5.1), P < 0.001) but similar incidence of CD-III ~ IV complications compared to ECA (3.4% vs 2.1%, RR from IPTW = 1.2 (95%CI: 0.4-4.0), P = 0.73). In ICA group, choosing another incision rather than lengthening main port site decreased the incidence of wound infection although without statistical significance (17.3% (14/81) versus 7.9% (3/38), crude RR = 2.2 (95%CI: 0.7-7.2), P = 0.17).

CONCLUSION

ICA is likely to be associated with higher risk of abdominal infection and CD-I ~ II complications.

Long-term oncologic outcome of D3 lymph node dissection for clinical stage 2/3 right-sided colon cancer

PURPOSE

To investigate oncologic outcomes including overall survival and disease-free survival depending on the extent of lymphadenectomy (D3 versus D2) by comparing D3 and D2 lymphadenectomy in patients with clinical stage 2/3 right colon cancer.

METHODS

Consecutive series of patients who underwent radical resection for right colon cancer at our three hospitals between January 2015 and June 2018 were retrospectively analyzed. Study cohorts were divided into two groups: D3 group and D2 group. Oncologic, pathologic, and perioperative outcomes of the two groups were compared.

RESULTS

A total of 295 patients (167 in the D2 group and 128 in the D3 group) were included in this study. Patients' characteristics showed no significant difference between the two groups. The median number of harvested lymph nodes was significantly higher in the D3 group than in the D2 group. The rate of complications was not significantly different between the two groups except for chyle leakage, which was more frequent in the D3 group. Five-year disease-free survival was 90.2% (95% CI: 84.8-95.9%) in the D3 group, which was significantly (p = 0.028) higher than that (80.5%, 95% CI: 74-87.5%) in the D2 group. There was no significant difference in overall survival between the two groups.

CONCLUSION

Our results indicate that D3 lymphadenectomy is associated with more favorable 5-year disease-free survival than D2 lymphadenectomy for patients with stage 2/3 right-sided colon cancer. D3 lymphadenectomy might improve oncologic outcomes in consideration of the recurrence rate.

Comparing the techniques and outcomes of laparoscopic transverse colectomy to laparoscopic hemicolectomy in mid-transverse colon cancer resection

Introduction

The mid-transverse colon cancer is relatively uncommon in all colon cancers and the optimal surgical approach of mid-transverse colon cancer remains debatable.

Aim and Objectives

Our study aimed to depict the techniques and outcomes of laparoscopic transverse colectomy in one single clinical center and compare this surgical approach to traditional laparoscopic right hemicolectomy and laparoscopic left hemicolectomy.

Method

This was a retrospective cohort study of patients with mid-transverse colon cancer in one single clinical center from February 2012 to October 2020. The enrolled patients were divided into two groups undergoing laparoscopic transverse colectomy and laparoscopic right/left hemicolectomy, respectively. The intraoperative, postoperative complications, oncological outcomes and functional outcomes were compared between the two groups. The primary endpoint was disease free survival (DFS).

Results

The study enrolled 70 patients with 40 patients undergoing laparoscopic transverse colectomy and 30 patients undergoing laparoscopic hemicolectomy. The intraoperative accidental hemorrhage and multiple organ resection occurred similarly in the two groups. In transverse colectomy, caudal-to-cephalic approach was likely to harvest more lymph nodes although require more operation time than cephalic-to-caudal approach (23.1 ± 14.3 vs. 13.4 ± 5.4 lymph nodes, P = 0.004; 184.3 ± 37.1 min vs. 146.3 ± 44.4 min, P = 0.012). The laparoscopic transverse colectomy was marginally associated with lower incidence of overall postoperative complications and shorter postoperative hospital stay although without statistical significance (8(20.0%) vs. 12(40.0%), P = 0.067; 7(5-12) vs. 7(5-18), P = 0.060). The 3-year DFS showed no significant difference (3-year DFS 89.7% in transverse colectomy vs. 89.9% in hemicolectomy, P = 0.688) between the two groups. The alternating consistency of defecation occurred significantly less after laparoscopic transverse colectomy than laparoscopic hemicolectomy (15(51.7%) vs. 20(80.0%), P = 0.030).

Conclusion

The laparoscopic transverse colectomy is technically feasible with satisfactory oncological and functional outcomes for mid-transverse colon cancer. Performing the caudal-to-cephalic approach might be more advantageous in lymphadenectomy.

Role of preoperative CT angiography with multimodality imaging reconstruction to perform laparoscopic Complete Mesocolic Excision (CME) and Central Vascular Ligation (CVL) in right-sided colon cancer: Is it really useful? A prospective clinical study

BACKGROUND

The concept of complete mesocolic excision (CME) and central vascular ligation (CVL) in right colonic resections appears to improve the oncological outcomes. The highest rate of complications reported in the literature in patients undergoing CME is related to difficult surgical manuevers and intraoperative bleeding due to the central vascular dissection.

METHODS

We used preoperative findings obtained with the CT angiography, multiplanar reformation (MPR), maximum intesity projection (MIP) and 3D volume rendering (VR) technique to verify if this preoperative radiological assessment had significant benefits regarding the difficulty of dissection of the embryological planes, the identification of vascular structures and central lymph nodes with reduction in mean operative time, intraoperative complications and better short-term outcomes versus standard contrast enhanced CT scan. We also have administered a questionnaire to investigate the subjective responses on the degree of difficulty of the surgical procedure both by the surgical team expert in CME and by a group of young surgeons.

RESULTS

Statistical analysis showed that overall operative time was significant shorter in patients underwent to radiological assessment (224,5 min; range 160-300 versus 252,6 min; range 200-340; p-value 0.023) with a significant lower rate of intraoperative complication (2.7% versus 4.2%; p-value 0.043). No differences were reported with respect to blood loss, conversion rate, anastomotic leakage or other surgical results. Analysis of the questionnaire underlined a progressive awareness of the correspondence between the radiological imaging and the surgical field.

CONCLUSION

The possibility of identifying the characteristics and course of the vascular structures along the axis of the superior mesenteric vessels certainly increases the surgeon's knowledge of the operating field, making him more confident with surgical maneuvers and significantly reducing the duration of the operating time and intraoperative complications.

Mid-term oncological outcomes after complete versus conventional mesocolic excision for right-sided colon cancer: a propensity score matching analysis

BACKGROUND

The correct extent of mesocolic dissection for right-sided colon cancer (RCC) is still under debate. Complete mesocolic excision (CME) has not gained wide diffusion, mainly due to its technical complexity and unclear oncological superiority. This study aims to evaluate oncological outcomes of CME compared with non-complete mesocolic excision (NCME) during resection for I-III stage RCC.

METHOD

Prospectively collected data of patients who underwent surgery between 2010 and 2018 were retrospectively analysed. 1:1 Propensity score matching (PSM) was used to balance baseline characteristics of CME and NCME patients. The primary endpoint of the study was local recurrence-free survival (LRFS). The two groups were also compared in terms of short-term outcomes, distant recurrence-free survival, disease-free survival, and overall survival.

RESULTS

Of the 444 patients included in the study, 292 were correctly matched after PSM, 146 in each group. The median follow-up was 45 months (IQR 33-63). Conversion rate, complications, and 90-day mortality were comparable in both groups. The median number of lymph nodes harvested was higher in CME patients (23 vs 19, p = 0.034). 3-year LRFS rates for CME patients was 100% and 95.6% for NCME (log-rank p = 0.028). At 3 years, there were no differences between the groups in terms of overall survival, distant recurrence-free survival, and disease-free survival.

CONCLUSION

Our PSM cohort study shows that CME is safe, provides a higher number of lymph nodes harvested, and is associated with better local recurrence-free survival.

Risk factors of central area lymph nodes metastasis for guiding optimal right colon cancer surgery: A retrospective multicenter study.. [DOI: 10.21203/rs.3.rs-1991182/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0]

Background: D3 or CME lymphadenectomy for right colon cancer (RCC) with lymph nodes metastasis (LNM) is strongly recommended but the anatomical landmark remains controversial. Central LNM predicted poor prognosis in RCC and determined the extent of lymphadenectomy. Methods: Data for 1712 RCC patients treated with D3/CME lymphadenectomy were reviewed. These patients had been treated in 9 centers. A total of 1023 RCC patients were enrolled in the derivation cohort while 689 patients were enrolled in the validation cohort. Results: The overall central LNM incidence was 12.58% (215/1712). In the derivation cohort, univariate and multivariate cox regression analyses revealed that preoperative N staging based on CT scan (OR=7.85, 95% CI, 4.53-14.51, p<0.001), tumor differentiation (OR=0.53, 95% CI, 0.33-0.86, p=0.01) and intraoperative view of tumor movability (OR=0.53, 95% CI, 0.33-0.86, p=0.02) were significant independent factors. Areas under receiver-operating characteristic curves (AUC) for assessing central LNM in the derivation and validation cohorts were 0.802 and 0.750, respectively. The risk-scoring system for patients with RCC was also established. A score of 0 points was the optimal cut-off value for central LNM. Compared to patients in the low-risk group, patients in the high-risk group exhibited worse overall survival outcomes (p<0.001).Conclusions: The established model can be used for preoperative assessment of the risk of central LNM in RCC patients, and for determining the landmark for D3/CME lymphadenectomy, therefore might contribute to decreased therapeutic complications and improved clinical outcomes.

Consensus statements on complete mesocolic excision for right-sided colon cancer-technical steps and training implications

Background

CME is a radical resection for colon cancer, but the procedure is technically demanding with significant variation in its practice. A standardised approach to the optimal technique and training is, therefore, desirable to minimise technical hazards and facilitate safe dissemination. The aim is to develop an expert consensus on the optimal technique for Complete Mesocolic Excision (CME) for right-sided and transverse colon cancer to guide safe implementation and training pathways.

Methods

Guidance was developed following a modified Delphi process to draw consensus from 55 international experts in CME and surgical education representing 18 countries. Domain topics were formulated and subdivided into questions pertinent to different aspects of CME practice. A three-round Delphi voting on 25 statements based on the specific questions and 70% agreement was considered as consensus.

Results

Twenty-three recommendations for CME procedure were agreed on, describing the technique and optimal training pathway. CME is recommended as the standard of care resection for locally advanced colon cancer. The essential components are central vascular ligation, exposure of the superior mesenteric vein and excision of an intact mesocolon. Key anatomical landmarks to perform a safe CME dissection include identification of the ileocolic pedicle, superior mesenteric vein and root of the mesocolon. A proficiency-based multimodal training curriculum for CME was proposed including a formal proctorship programme.

Conclusions

Consensus on standardisation of technique and training framework for complete mesocolic excision was agreed upon by a panel of experts to guide current practice and provide a quality control framework for future studies.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00464-021-08395-0.

The Mesentery in Complete Mesocolic Excision

The following article summarizes technical aspects of how to operate in the mesentery during complete mesocolic excision (CME). Increasingly, CME is being adopted and as such it is important to establish the anatomical basis of the techniques involved. This review thus serves to provide that foundation and explains the surgical techniques built on it.

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.

The Medial Border of Laparoscopic D3 Lymphadenectomy for Right Colon Cancer: Results from an Exploratory Pilot Study

BACKGROUND

Opinions vary on the medial border of D3 lymphadenectomy for right colon cancer. Most surgeons place the medial border along the left side of the superior mesenteric vein, but some consider the left side of the superior mesenteric artery as the medial border.

OBJECTIVES

This study investigated the clinical outcomes of laparoscopic D3 lymphadenectomy for right colon cancer with the medial border along the left side of superior mesenteric artery.

DESIGN

This was a retrospective study.

SETTINGS

The study was conducted in specialized colorectal cancer department of 5 tertiary hospitals.

PATIENTS

Patients receiving laparoscopic D3 lymphadenectomy for right colon cancer from January 2013 to December 2018 were included.

MAIN OUTCOME MEASURES

After propensity score matching, 307 patients receiving laparoscopic D3 lymphadenectomy along the left side of the superior mesenteric artery were assigned to the superior mesenteric artery group and 614 patients were assigned to the superior mesenteric vein group. Univariate, multivariate, and Kaplan-Meier analyses were performed to assess the clinical data.

RESULTS

The short-term outcomes were similar between the 2 groups; however, the superior mesenteric artery group had a higher rate of chylous leakage (p < 0.001). More lymph nodes were harvested from the superior mesenteric artery group than from the superior mesenteric vein group (p = 0.001). The number (p = 0.005) of metastatic lymph nodes and the lymph node ratio (p = 0.041) in main nodes were both higher in the superior mesenteric artery group. The 2 groups had similar long-term survival, but the superior mesenteric artery group tended to show better disease-free survival in patients with stage disease III (p = 0.056).

LIMITATIONS

This was a retrospective, nonrandomized study.

CONCLUSION

Laparoscopic D3 lymphadenectomy along the left side of the superior mesenteric artery, except for a higher rate of chylous leakage, had short-term outcomes comparable to the superior mesenteric vein group. The superior mesenteric artery group tended to achieve better disease-free survival in patients with stage III disease, but further study is required to better elucidate differences in these approaches because risks/benefits do exist.

Proper surgical extent for clinical Stage I right colon cancer

Purpose:

Pre-operative evaluation identifying clinical-stage affects the decision regarding the extent of surgical resection in right colon cancer. This study was designed to predict a proper surgical resection through the prognosis of clinical Stage I right colon cancer.

Patients and Methods:

We included patients who were diagnosed with clinical and pathological Stage I right-sided colon cancer, including appendiceal, caecal, ascending, hepatic flexure and proximal transverse colon cancer, between August 2010 and December 2016 in two tertiary teaching hospitals. Patients who underwent open surgeries were excluded because laparoscopic surgery is the initial approach for colorectal cancer in our institutions.

Results:

Eighty patients with clinical Stage I and 104 patients with pathological Stage I were included in the study. The biopsy reports showed that the tumour size was larger in the clinical Stage I group than in the pathological Stage I group (3.4 vs. 2.3 cm, P < 0.001). Further, the clinical Stage I group had some pathological Stage III cases (positive lymph nodes, P = 0.023). The clinical Stage I group had a higher rate of distant metastases (P = 0.046) and a lower rate of overall (P = 0.031) and cancer-specific survival (P = 0.021) than the pathological Stage I group. Compared to pathological Stage II included in the period, some of the survival curves were located below the pathological Stage II, but there was no statistical difference.

Conclusion:

The study results show that even clinical Stage I cases, radical resection should be considered in accordance with T3 and T4 tumours.

Mesenteric closure with polymer-ligating clips after right colectomy with complete mesocolic excision for cancer and mesentery-based ileocolic resection for Crohn's disease

Mesenteric closure following right colectomy remains controversial and, following the advent of laparoscopic surgery, many surgeons do not routinely close the mesentery after colorectal resection. Nevertheless, especially after the introduction of operations such as right colectomy with complete mesocolic excision and ileocolic resections with extensive mesentery removal for Crohn's disease, the wide mesenteric defect resulting from the dissections can certainly expose the patients to complications such as internal hernias or volvuli. In general, mesenteric closure requires intracorporeal suturing. We describe a simple technique for the closure of the mesentery after surgical resection using polymer-ligating clips. This novel technique seems to minimize the time, effort and risk inherent to the procedure, even after large mesenteric excisions.

Right hemicolectomy with complete mesocolic excision is safe, leads to an increased lymph node yield and to increased survival: results of a systematic review and meta-analysis

BACKGROUND

The introduction of complete mesocolic excision (CME) for right colon cancer has raised an important discussion in relation to the extent of colic and mesenteric resection, and the impact this may have on lymph node yield. As uncertainty remains regarding the usefulness of and indications for right hemicolectomy with CME and the benefits of CME compared with a traditional approach, the purpose of this meta-analysis is to compare the two procedures in terms of safety, lymph node yield and oncological outcome.

METHODS

We performed a systematic review of the literature from 2009 up to March 15th, 2020 according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Two hundred eighty-one publications were evaluated, and 17 met the inclusion criteria and were included. Primary endpoints analysed were anastomotic leak rate, blood loss, number of harvested lymph nodes, 3- and 5-year oncologic outcomes. Secondary outcomes were operating time, conversion, intraoperative complications, reoperation rate, overall and Clavien-Dindo grade 3-4 postoperative complications.

RESULTS

In terms of safety, right hemicolectomy with CME is not inferior to the standard procedure when comparing rates of anastomotic leak (RR 0.82, 95% CI 0.38-1.79), blood loss (MD -32.48, 95% CI -98.54 to -33.58), overall postoperative complications (RR 0.82, 95% CI 0.67-1.00), Clavien-Dindo grade III-IV postoperative complications (RR 1.36, 95% CI 0.82-2.28) and reoperation rate (RR 0.65, 95% CI 0.26-1.75). Traditional surgery is associated with a shorter operating time (MD 16.43, 95% CI 4.27-28.60) and lower conversion from laparoscopic to open approach (RR 1.72, 95% CI 1.00-2.96). In terms of oncologic outcomes, right hemicolectomy with CME leads to a higher lymph node yield than traditional surgery (MD 7.05, 95% CI 4.06-10.04). Results of statistical analysis comparing 3-year overall survival and 5-year disease-free survival were better in the CME group, RR 0.42, 95% CI 0.27-0.66 and RR 0.36, 95% CI 0.17-0.56, respectively.

CONCLUSIONS

Right hemicolectomy with CME is not inferior to traditional surgery in terms of safety and has a greater lymph node yield when compared with traditional surgery. Moreover, right-sided CME is associated with better overall and disease-free survival.

Regional lymph nodes distribution pattern in central area of right-sided colon cancer: in-vivo detection and the update on the clinical exploration

Distribution of regional lymph nodes (LNs) is decisive for the lymphadenectomy boundary in radical resection of right-sided colon cancer (RCC). Currently, the data of LNs in central area remains ambiguous and scarce. Herein we aim to provide a more detailed anatomical research on LNs surrounding the superior mesenteric vessels for RCC and investigated the metastasis rate. In this study, Carbon Nanoparticles (CNs) and Indocyanine Green (ICG) were used for regional LNs mapping by preoperative colonoscopic tattooing (PCT) and we laparoscopically observed the stained LNs distribution pattern. Lastly, 143 RCC patients who received a "superior mesenteric artery (SMA)-oriented" hemicolectomy were included to calculate the probability of LNs metastasis in our target area. 27 patients diagnosed as RCC (mean age 58.04 years, 17 male) were included. 14 patients underwent CNs injection and 13 patients consented to the ICG, while 4 cases suffered from imaging failure. The unequal number of the regional LNs located between SMV and SMA was detected in 22 cases (81.48%), posterior to SMV area in 6 cases (22.22%), and anterior to SMA in 16 cases (59.26%), respectively. The presence of LNs posterior to SMV was associated with the crossing pattern of ileocolic artery (χ² = 4.24, P = 0.039). The probability of LNs metastasis in the above areas (target areas) was 2.10% (3/143). In conclusion, right-hemi colon-draining lymphatic vessels anteriorly/posteriorly traversed the SMV and arrived at the surface of SMA near the middle colonic artery (MCA) level, which highlights the potential need of removing mesenteric tissue in our target area on lymphatic resection.

Complete mesocolic excision and D3 lymphadenectomy with central vascular ligation in right-sided colon cancer: a systematic review of postoperative outcomes, tumor recurrence and overall survival

BACKGROUND

In right-sided colon cancer surgery, currently there is a great deal of discussion and debate regarding complete mesocolic excision (CME) versus conventional right hemicolectomy (CRH) on postoperative outcomes and oncological results. Our aim was to perform a systematic review of the short- and long-term outcomes of CME to standardize surgical approach in patients with right-sided colon cancer.

METHODS

A systematic review was performed examining available data on randomized and non-randomized studies evaluating the role of CME and D3 lymphadenectomy in the treatment of right-sided colon cancer, in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) standards.

RESULTS

After literature search, 919 studies have been recorded, 110 studies underwent full-text reviews and 30 studies met inclusion criteria. The total number of CME procedures was 5931. Postoperative complications was reported in 28 studies with pooled overall complications of 1.88% for CME surgery. Six studies reported 0% of overall postoperative complications and they demonstrated a low incidence of complications following CME procedure. Anastomotic leak was reported in 27 studies with pooled proportion of 0.92% after CME resections. There were 16 papers reporting overall survival following CME procedure, with a mean of 85% of patients survived at 5 years. Mean 5-year overall survival was 93.05% in stage I patients, 89.76% in stage II patients and 79.65% in stage III patients. Local and distant recurrence were included in 21 studies, reporting tumor recurrence rate of 12.25% following CME. 5-year tumor recurrence was 5.8% in stage I patients, 7.68% in stage II patients and 15.69% in stage III patients.

CONCLUSIONS

CME does not increase the risk of postoperative complications and significantly improves the long-term oncological impact. Prospective multicentre studies results are needed to verify if CME could be considered standard surgery for right colon cancer.

Complete mesocolic excision versus conventional hemicolectomy in patients with right colon cancer: a systematic review and meta-analysis

PURPOSE

Complete mesocolic excision (CME) has introduced a promising surgical approach for treatment of right colon cancer. However, benefits of CME are still a matter of debate. We conducted a systematic review and meta-analysis to assess safety and long-term outcomes of CME versus conventional right hemicolectomy (CRH).

METHODS

We systematically searched MEDLINE, the Cochrane Database of Systematic Reviews, Scopus, Web of Science, and Embase for retrieving studies comparing CME with CRH in right colon cancer. After data extraction from the included studies, meta-analysis was performed to compare postoperative complications, anastomotic leakage, 30-day mortality, number of lymph node yield, disease-free survival (DFS), and overall survival (OS).

RESULTS

Eight studies met the inclusion criteria with a total of 1871 patients enrolled. No difference was observed in postoperative complications (OR 1.13, 95% CI 0.88-1.47, p = 0.34). CME was associated with significantly higher number of lymph nodes retrieved (MD 9.17, CI 4.67-13.68, p < 0.001). CME also improved 3-year OS (OR 1.57, 95% CI 1.17-2.11, p = 0.003), 5-year OS (OR 1.41, 95% CI 1.06-1.89, p = 0.02), and 5-year DFS (OR 1.99, 95% CI 1.29-3.07, p = 0.002). A sub-group analysis for patients with stage III colon cancer showed no significant impact of CME on 3-year and 5-year OS (OR 2.47, 95% CI 0.86-7.06, p = 0.09; OR 1.23, 95% CI 0.78-1.94, p = 0.38).

CONCLUSION

Although with limited evidence, CME shows similar postoperative complication rates and an improved survival outcome compared with CRH.

The Application of Core Needle Biopsy Through the Trocar Hole in the Surgical Operation of Endoscopically Unresectable Giant Colon Polyps: A Systematic Review Study

INTRODUCTION

The study aimed to investigate the application of core needle biopsy through the trocar hole during surgery on endoscopically unresectable giant colon polyps.

METHODS

The clinical data of 51 patients with endoscopically unresectable giant colon polyps from May 2016 to May 2020 were retrospectively analyzed. The primary observational outcomes were two comparative analyses of pathologic results, using the kappa index: comparison of the pathologic results from the preoperative colonoscopy and the postoperative pathologic results and comparison of the intraoperative pathologic results from core needle biopsy of the intestinal wall and the postoperative pathologic results. The secondary observational outcomes were duration of needle biopsy, operation duration, volume of intraoperative hemorrhage, rate of postoperative wound infection, rate of abdominal cavity infection, length of stay, and number and positivity of lymph node dissections after laparoscopic radical resection of colon cancer.

RESULTS

Poor consistency was found between the preoperative (colonoscopy) and postoperative pathologic results, with kappa = 0.222 (i.e., kappa < 0.4), P < 0.05. However, good consistency was found between the intraoperative (core needle biopsy) and postoperative pathologic results, with kappa = 0.923 (i.e., kappa ≥ 0.75), P < 0.05. The postoperative pathologic results were as follows: 7 cases of adenomatous polyps of the colon, 12 cases of low-grade intraepithelial neoplasia, 12 cases of high-grade intraepithelial neoplasia, and 25 cases of invasive colon cancer. There was no incision infection, no abdominal cavity infection or formation of an abdominal abscess, no anastomotic leakage, and no death for any of the 51 patients. Postoperative complications occurred in two cases (3.92%).

CONCLUSION

Biopsy through the trocar hole during laparoscopic surgery produced highly accurate pathologic results and was a fast, safe, and effective diagnostic method. Pathologic results from intraoperative biopsy could accurately determine the nature of colon polyps and provide a basis for choosing an appropriate surgical scheme.

Impact of D3 lymph node dissection on upstaging and short-term survival in clinical stage I right-sided colon cancer

BACKGROUND

D3 lymph node dissection is becoming the standard procedure for the treatment of advanced right colon cancer and has shown increasing evidence of its oncologic benefit. However, a clear indication for its application is lacking and data on this topic is unsatisfactory. Thus, the necessity for D3 lymph node dissection in clinical stage I right colon cancer remains controversial.

METHODS

We retrospectively analyzed data from clinical stage I right colon cancer patients who underwent radical surgery at three hospitals of Korea university medical center between January 2015 and June 2018. We compared surgical complications and short-term oncologic outcomes between D2 and D3 lymph node dissections in these patients.

RESULTS

Among 512 patients, 122 (23.8%) were clinical stage I. Of these, 88 and 34 patients received D2 and D3 lymph node dissection, respectively. There were no statistically significant differences in clinicopathologic variables and surgical outcomes between the two groups. Upstaging occurred in 16 patients (47.1%) in the D3 group and 23 patients (26.1%) in the D2 group. There were four recurrences in the D2 group but no recurrence in the D3 group. Log-rank tests showed no statistically significant difference in disease-free survival rates between the two groups (p = 0.210).

CONCLUSION

There was no significant difference in disease-free survival rates between D2 and D3 lymph node dissection in clinical stage I right colon cancer patients. However, recurrence occurred in the D2 group. Efforts to improve the accuracy of clinical staging are required and more studies with better quality are needed.

Short-term outcomes of complete mesocolic excision versus D2 dissection in patients undergoing laparoscopic colectomy for right colon cancer (RELARC): a randomised, controlled, phase 3, superiority trial

BACKGROUND

Whether extended lymphadenectomy for right colon cancer leads to increased perioperative complications or improves survival is still controversial. This trial aimed to compare the efficacy and safety of complete mesocolic excision (CME) versus D2 dissection in laparoscopic right hemicolectomy for patients with right colon cancer. This article reports the early safety results from the trial.

METHODS

This randomised, controlled, phase 3, superiority, trial was done at 17 hospitals in nine provinces of China. Eligible patients were aged 18-75 years with histologically confirmed primary adenocarcinoma located between the caecum and the right third of the transverse colon, without evidence of distant metastases. Central randomisation was done by means of the Clinical Information Management-Central Randomisation System via block randomisation (block size of four). Patients were randomly assigned (1:1) to CME or D2 dissection during laparoscopic right colectomy. Central lymph nodes were dissected in the CME but not in the D2 procedure. Neither investigators nor patients were masked to their group assignment but the quality control committee were masked to group assignment. The primary endpoint was 3-year disease-free survival, but the data for this endpoint are not yet mature; thus, only the secondary outcomes-intraoperative surgical complications and postoperative complications within 30 days of surgery, graded according to the Clavien-Dindo classification, mortality (death from any cause within 30 days of surgery), and central lymph node metastasis rate in the CME group only-are reported in this Article. This early analysis of safety was preplanned. The outcomes were analysed according to a modified intention-to-treat principle (excluding patients who no longer met inclusion criteria after surgery or who did not have surgery). This study is registered with ClinicalTrials.gov, NCT02619942. Study recruitment is complete, and follow-up is ongoing.

FINDINGS

Between Jan 11, 2016, and Dec 26, 2019, 1072 patients were enrolled and randomly assigned. After exclusion of 77 patients, 995 patients were included in the modified intention-to-treat population (495 in the CME group and 500 in the D2 dissection group). The postoperative surgical complication rate was 20% (97 of 495 patients) in the CME group versus 22% (109 of 500 patients) in the D2 group (difference, -2·2% [95% CI -7·2 to 2·8]; p=0·39); the frequency of Clavien-Dindo grade I-II complications were similar between groups (91 [18%] vs 92 [18%], difference, -0·0% [95% CI -4·8 to 4·8]; p=1·0) but Clavien-Dindo grade III-IV complications were significantly less frequent in the CME group than in the D2 group (six [1%] vs 17 [3%], -2·2% [-4·1 to -0·3]; p=0·022); no deaths occurred in either group. Of the intraoperative complications, vascular injury was significantly more common in the CME group than in the D2 group (15 [3%] vs six [1%], difference, 1·8 [95% CI 0·04 to 3·6]; p=0·045). Metastases in the central lymph nodes were detected in 13 (3%) of 394 patients who underwent central lymph node biopsy in the CME group; no patient had isolated metastases to central lymph nodes.

INTERPRETATION

Although the CME procedure might increase the risk of intraoperative vascular injury, it generally seems to be safe and feasible for experienced surgeons.

FUNDING

The Capital Characteristic Clinical Project of Beijing and the Chinese Academy of Medical Sciences.

Incidence of and Risk Factors for Gastroepiploic Lymph Node Involvement in Patients with Cancer of the Transverse Colon Including the Hepatic Flexure

BACKGROUND

To define the incidence of gastroepiploic lymph node (GLN) metastasis in patients with cancer of the transverse colon, including the hepatic flexure, and to identify the preoperative predictors of GLN involvement in a large-volume center in China.

METHODS

This retrospective monocentric cross-sectional study respected the STROBE statement. Of 3208 consecutive patients who underwent colon cancer resection, a total of 371 patients with cancer of the transverse colon including the hepatic flexure who underwent complete mesocolic excision and GLN resection in our center were retrospectively reviewed between November 2010 and November 2017. Logistic regression was performed to identify predictors of GLN metastasis. Endoscopic obstruction was defined as a luminal obstruction of the colon severe enough to prevent the colonoscope from passing beyond the tumor regardless of the presenting symptoms.

RESULTS

The GLN involvement rate was 4.0 (2.0-6.1)%. Patients who had GLN involvement had a significantly higher rate of endoscopic obstruction (P = 0.030), higher rate of signet ring adenocarcinoma or lymphovascular invasion (P < 0.05), higher preoperative CEA level (P = 0.037), more advanced pN stage (P < 0.001) and more advanced M stage (P = 0.003) than the patients without GLN involvement. ROC curve analyses showed that the cutoff value for CEA was 17.0 ng/ml (46.7% sensitivity, 84.3% specificity, P = 0.037) for the prediction of GLN metastasis. Multivariate analysis showed that endoscopic obstruction, signet ring adenocarcinoma, a CEA level ≥17 ng/ml and M1 stage were independently correlated with the GLN metastasis.

CONCLUSION

The incidence rate of GLN metastasis was low. To the best of our knowledge, the present study was the first to evaluate the preoperative predictors of GLN metastasis. Combinations of predictive factors may be useful for stratifying patients at high risk of GLN metastasis.

Robotic Complete Mesocolic Excision (CME) is a safe and feasible option for right colonic cancers: short and midterm results from a single-centre experience

BACKGROUND

Complete mesocolic excision (CME) for right colon cancers has traditionally been an open procedure. Surgical adoption of minimal access CME remains limited due to the technical challenges, training gaps and lack of level-1 data for proven benefits. Currently there is limited published data regarding the clinical results with the use of robotic CME surgery. Aim To report our experience, results and techniques, highlighting a clinical and oncological results and midterm oncological outcomes for robotic CME.

AIM

To report our experience, results and techniques, highlighting a clinical and oncological results and midterm oncological outcomes for robotic CME.

METHODS

All patients undergoing standardised robotic CME technique with SMV first approach between January 2015 and September 2019 were included in this retrospective review of a prospectively collected database. Patient demographics, operative data and clinical and oncological outcomes were recorded.

RESULTS

Seventy-seven robotic CME resections for right colonic cancers were performed over a 4-year period. Median operative time was 180 (128-454) min and perioperative blood loss was 10 (10-50) ml. There were 25 patients who had previous abdominal surgery. Median postoperative hospital stay was 5 (3-18) days. There was no conversion to open surgery in this series. Median lymph node count was 30 (10-60). Three (4%) patients had R1 resection. There was one (1%) local recurrence in stage III disease and 4(5%) distal recurrence in stage II and stage III. There was no 30- or 90-day mortality. Three-year disease-free survival was 100%, 91.7% and 92% for stages I, II and III, respectively. Overall survival was 94%.

CONCLUSIONS

Robotic CME is feasible, effective and safe. Good oncological results and improved survival are seen in this cohort of patients with a standardised approach to robotic CME.

A global systematic review and meta-analysis on laparoscopic vs open right hemicolectomy with complete mesocolic excision

PURPOSE

The aim of this study was to compare the outcomes of right hemicolectomy with CME performed with laparoscopic and open surgery.

METHODS

PubMed, Scopus, Web of Science, China National Knowledge Infrastructure, Wanfang Data, Google Scholar and the ClinicalTrials.gov register were searched. Primary outcome was the overall number of harvested lymph nodes. Secondary outcomes were short and long-term course variables. A meta-analysis was performed to calculate risk ratios.

RESULTS

Twenty-one studies were identified with 5038 patients enrolled. The difference in number of harvested lymph nodes was not statistically significant (MD 0.68, - 0.41-1.76, P = 0.22). The only RCT shows a significant advantage in favour of laparoscopy (MD 3.30, 95% CI - 0.20-6.40, P = 0.04). The analysis of CCTs showed an advantage in favour of the laparoscopic group, but the result was not statically significantly (MD - 0.55, 95% CI - 0.57-1.67, P = 0.33). The overall incidence of local recurrence was not different between the groups, while systemic recurrence at 5 years was lower in laparoscopic group. Laparoscopy showed better short-term outcomes including overall complications, lower estimated blood loss, lower wound infections and shorter hospital stay, despite a longer operative time. The rate of anastomotic and chyle leak was similar in the two groups.

CONCLUSIONS

Despite the several limitations of this study, we found that the median number of lymph node harvested in the laparoscopic group is not different compared to open surgery. Laparoscopy was associated with a lower incidence of systemic recurrence.

Is radical surgery for clinical stage I right-sided colon cancer relevant? A retrospective review

Purpose

Radical lymph node dissection for right-sided colon cancer is technically challenging. No clear guideline is available for surgical resection of clinical stage I right-sided colon cancer. This study was designed to review the pathologic stage of clinical stage I right-sided colon cancer and determine the relevant extent of surgical resection.

Methods

Patients were treated for clinical stage I right-sided colon cancers (cecal, ascending, hepatic flexure, and proximal transverse colon) between July 2006 and December 2014 at a tertiary teaching hospital. Open surgery was not included because laparoscopic surgery is an initial major procedure in the institution.

Results

During the study period, 80 patients diagnosed with clinical stage I right-sided colon cancer were classified into 2 groups according to the pathology: stage 0/I and II/III. Tumor sizes were larger in the stage II/III group (P = 0.003). The stage II/III group had higher rates of vascular (P = 0.023) and lymphatic invasion (P = 0.023) and lower rates of well differentiation (P = 0.022). During follow-up, 1 case of local and 4 cases of systemic recurrences were found. Multivariate analysis to confirm odds ratios affecting change from clinical stage I to pathological stage II/III showed that tumor size (P = 0.010) and the number of retrieved lymph nodes (P = 0.046) were risk factors.

Conclusion

For right-sided colon cancer, even with clinical stage I included, radical lymph node dissection should be performed for exact staging with sufficient number of lymph nodes. This will help determine appropriate adjuvant treatment, especially in large tumor sizes.

A Systematic Review and Meta-Analysis of Single-Incision Versus Multiport Laparoscopic Complete Mesocolic Excision Colectomy for Colon Cancer

Background. Our aim was to compare the emerging technique of single-incision laparoscopic surgery complete mesocolic excision (SILS CME) colectomy with the standard multiport laparoscopic CME (MPL CME) colectomy. Methods. MEDLINE (PubMed), Scopus, EMBASE, Ovid, and the Cochrane library were searched. Studies comparing the SILS CME with MPL CME in adults with colon adenocarcinoma were included. The Jadad and Newcastle Ottawa Scales were used to critically appraise the studies. The presence of statistical heterogeneity or publication bias was examined. Results. Seven studies (3 randomized) with a total number of 1344 patients were included (546 SILS CME and 798 MPL CME). No difference was found in anastomotic leakage (odds ratio [OR] = 0.79 [0.31 to 2.03]; P = .63), number of lymph nodes (weighted mean difference [WMD] = 0.85 [-0.97 to 2.66]; P = .36), hospital stay (WMD = 0.01 [-0.19 to 0.20]; P = .96), overall survival (hazard ratio [HR] = 1.19 [0.29 to 4.80]; P = .81), and disease-free survival (HR = 1.30 [0.30 to 5.61]; P = .72). Skin incision was shorter in SILS CME group (WMD = -3.02 [-3.25 to -2.80]; P < .00001) but with no difference in pain reported in postoperative day 1 (standardized mean difference [SMD] = -0.21 [-0.50 to 0.09]; P = .17) or day 2 (SMD = 0.16 [-0.52 to 0.84]; P = .64). Conclusions. SILS CME, although technically more demanding, has equivalent short- and long-term outcomes when compared with MPL CME. Potential benefits in cosmesis or postoperative pain need to be further explored by high-quality randomized controlled trials.

Robotic Complete Mesocolic Excision Versus Conventional Laparoscopic Hemicolectomy for Right-Sided Colon Cancer

Background: Robotic technique has been proposed to overcome the limitations of laparoscopic surgery. In this study, we aimed at determining whether robotic complete mesocolic excision (CME) for right-sided colon cancer can be safe and effective as conventional laparoscopic right hemicolectomy (CLRH). Materials and Methods: Between February 2015 and September 2017, patients undergoing robotic right CME and CLRH with curative intent for right-sided colon cancer were included. Patient characteristics, short-term and histopathological outcomes were compared between the groups. Results: Ninety-six patients (robotic, n = 35) were included in this study. The operative time (286 ± 77 versus 132 ± 40 minutes, P = .0001) was significantly longer in the robotic group. There were no conversions in either group. No significant differences existed between the groups regarding the mean estimated blood loss, time to first flatus, length of hospital stay (6 ± 3 versus 6 ± 3 days, P = .64), and follow-up times (robotic 15 ± 8 versus laparoscopic 16 ± 10 months P = .11). Overall complication rates (n = 10 [29%] versus n = 15 [25%], P = .67) were similar. In the robotic group, vascular injury occurred in 2 patients, and both were repaired robotically. The mean number of harvested lymph nodes was significantly higher (41 ± 12 versus 33 ± 10, P = .04) and length between the vascular tie and colonic wall was longer (13 ± 3.5 versus 11 ± 3, P = .02) in the robotic group. Conclusion: Although robotic right CME seems equally safe to CLRH in terms of short-term morbidity, future prospective randomized trials are needed to define its role for treatment of right colectomy.

Biology-Based Surgery: The Extent of Lymphadenectomy in Cancer of the Colon

The progression of colon cancer (CC) involves hematogenous and lymphatic spread to locoregional lymph nodes (LN), distant LN, and metastatic sites including the liver. The biological mechanisms that govern CC progression remain elusive. The Halsted model assumes an orderly, stepwise progression from the primary tumor to nearby nodes, henceforth to anatomically more distant nodes, and ultimately to distant organs. The Fisher model, on the other hand, regards the release of metastatic cells as early and essentially random events. The underlying biology has important implications for the ideal extent of surgery: when the Fisher model is correct, efforts to remove apical (central), extramesenteric, or para-aortic LN are unlikely to affect the oncological outcome. Recent data from phylogenetic studies suggest that cancer cell populations differ genetically among different LN stations and from distant metastases. Circulating tumor cells and other liquid biomarkers can be detected in the circulation of patients with early-stage disease. Local recurrence in CC is uncommon, and it is associated with a high risk of systemic progression and poor survival. Clinical studies comparing standard colectomy with extensive surgery (high ligation of the inferior mesenteric artery, complete mesocolic excision, D3 dissection, and para-aortic or extramesenteric node dissection) show that these techniques increase the LN count, while any beneficial effect on the risk of local recurrence or disease-free survival is at present uncertain due to the lack of controlled trials. Ongoing randomized trials comparing extensive vs. standard surgery for CC will generate important answers.

Minimally Invasive Surgical Approaches to Colon Cancer

Colon cancer remains the most common abdominal visceral malignancy affecting both men and women in America. Open colectomy has been the standard of care for colon cancer patients the past 100 years; although highly effective, the major trauma associated with it has a significant morbidity rate and represents a large operation for patients to recover from. Minimally invasive colon surgery was developed as a new and alternative option, and surgeons aim to continue to make it simpler, more reproducible, and easier to teach and learn. We describe herein the current state of minimally invasive colorectal surgery for colon cancer and compare it with open surgery to offer insights to future directions.

Variations of Gastrocolic Trunk of Henle and Its Significance in Gastrocolic Surgery

Due to the increasing incidence of gastrointestinal (GI) tumors, more and more importance is attached to radical resection and patients' survival, which requires adequate extent of resection and radical lymph node dissection. Blood vessels around the gastrointestinal tract, as anatomical landmarks for tumor resection and lymph node dissection, play a key role in the successful surgery and curative treatment of gastrointestinal tumors. In the isolation of subpyloric area or hepatic flexure of the colon for gastrectomy or right hemicolectomy, lymph node dissection and ligation are often performed at the head of the pancreas and superior mesenteric vein, during which even a minor inadvertent error may lead to unwanted bleeding. Among these blood vessels, the venous system composed of Henle's trunk and its tributaries is the most complex, which has a direct influence on the outcome and postoperative recovery of the patients. There are many variations of Henle's trunk, with complicated courses and various locations, attracting more and more researchers to study it and tried to analyze the influence of its variations on gastrointestinal surgeries. We characterized various variants and tributaries of Henle's trunk using autopsy, vascular casting, 3D CT reconstruction, intraoperative anatomy, and Hisense CAS system and summarized and analyzed the tributaries of Henle's trunk, to determine its influence on GI surgeries.

Surgical Anatomy of the Superior Mesenteric Vessels Related to Colon and Pancreatic Surgery: A Systematic Review and Meta-Analysis

The surgeon dissecting the base of the mesenterium, around the superior mesenteric vein (SMV) and artery, is facing a complex tridimensional vascular anatomy and should be aware of the anatomical variants in this area. The aim of this systematic review is to propose a standardized terminology of the superior mesenteric vessels, with impact in colon and pancreatic resections. We conducted a systematic search in PubMed/MEDLINE and Google Scholar databases up to March 2017. Forty-five studies, involving a total of 6090 specimens were included in the present meta-analysis. The pooled prevalence of the ileocolic, right colic and middle colic arteries was 99.8%, 60.1%, and 94.6%, respectively. The superior right colic vein and Henle trunk were present in 73.9%, and 89.7% of specimens, respectively. In conclusion, the infra-pancreatic anatomy of the superior mesenteric vessels is widely variable. We propose the term Henle trunk to be used for any venous confluence between gastric, pancreatic and colic veins, which drains between the inferior border of the pancreas and up to 20 mm downward on the right-anterior aspect of the SMV. The term gastrocolic trunk should not be synonymous, but a subgroup of the Henle trunk, together with to gastropancreatocolic, gastropancreatic, or colopancreatic trunk.

Safety, quality and effect of complete mesocolic excision vs non-complete mesocolic excision in patients with colon cancer: a systemic review and meta-analysis

AIM

The application of complete mesocolic excision (CME) in colon cancer is controversial. We performed a meta-analysis to compare the safety, quality and effect of CME with non-complete mesocolic excision (NCME) in patients with colon cancer.

METHOD

We searched PubMed, ScienceDirect, the Cochrane Library and Scopus to identify studies comparing CME with NCME in colon cancer. We focused on three study outcome areas: safety (operation time, blood loss, complications, mortality); quality (large bowel length, distance from the tumour to the high vascular tie, area of mesentery, total lymph nodes); and effect (long-term survival).

RESULTS

A total of 8586 patients from 12 studies were included in the meta-analysis. CME was associated with greater intra-operative blood loss [weighted mean difference (WMD) 79.87, 95% CI: 65.88-93.86], more postoperative surgical complications (relative risk 1.23, 95% CI: 1.08-1.40), longer large bowel resection (WMD 47.06, 95% CI: 10.49-83.62), greater distance from the tumour to the high vascular tie (WMD 17.51, 95% CI: 15.16-19.87), larger area of mesentery (WMD 36.09, 95% CI: 18.06-54.13) and more lymph nodes (WMD 6.13, 95% CI: 1.97-10.28) than NCME. CME also had positive effects on 5-year survival [hazard ratio (HR) 0.33, 95% CI: 0.13-0.81], 3-year survival (HR 0.58, 95% CI: 0.39-0.86) and 3-year survival for Stage III disease (HR 0.69, 95% CI: 0.60-0.80) compared with NCME.

CONCLUSION

Limited evidence suggests that CME is a more effective strategy for improving specimen quality and survival but with a higher complication rate.