Complete Mesocolic Excision With Central Vascular Ligation in Comparison With Conventional Surgery for Patients With Colon Cancer - The Experiences at Two Centers

Clinical validation of 3D virtual modelling for laparoscopic complete mesocolic excision with central vascular ligation for proximal colon cancer

INTRODUCTION

Laparoscopic Complete Mesocolic Excision (CME) with Central Vascular Ligation (CVL) in colon cancer surgery has not been broadly adopted in part because of safety concerns. Pre-operative 3-D virtual modelling (3DVM) may help but needs validation.

METHODS

3DVM were routinely constructed from CT mesenteric angiograms (CTMA) using a commercial service (Visible Patient, Strasbourg, France) for consecutive patients during our CMECVL learning curve over three years. 3DVMs were independently checked versus CTMA and operative findings. CMECVL outcomes were compared versus other patients undergoing standard mesocolic excision (SME) surgery laparoscopically in the same hospital as control. Stakeholders were studied regarding 3DVM use and usefulness (including detail retention) versus CTMA and a physical 3D-printed model.

RESULTS

26 patients underwent 3DVM with intraoperative display during laparoscopic CMECVL within existing workflows. 3DVM accuracy was 96 % re arteriovenous variations at patient level versus CTMA/intraoperative findings including accessory middle colic artery identification in three patients. Twenty-two laparoscopic CMECVL with 3DVM cases were compared with 49 SME controls (age 69 ± 10 vs 70.9 ± 11 years, 55 % vs 53 % males). There were no intraoperative complications with CMECVL and similar 30-day postoperative morbidity (30 % vs 29 %), hospital stay (9 ± 3 vs 12 ± 13 days), 30-day readmission (6 % vs 4 %) and reoperation (0 % vs 4 %) rates. Intraoperative times were longer (215.7 ± 43.9 vs 156.9 ± 52.9 min, p=<0.01) but decreased significantly over time. 3DVM surveys (n = 98, 20 surgeons, 48 medical students, 30 patients/patient relatives) and comparative study revealed majority endorsement (90 %) and favour (87 %).

CONCLUSION

3DVM use was positively validated for laparoscopic CMECVL and valued by clinicians, students, and patients alike.

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.

Efficacy and Feasibility of Complete Mesocolic Excision with Central Vascular Ligation in Complicated Colorectal Cancer

Complete mesocolic excision (CME) with central vascular ligation (CVL) involves sharp dissection through the embryological planes. However, it may be associated with high mortalities and morbidities especially in colorectal emergencies. This study aimed to investigate the outcomes of CME with CVL in complicated colorectal cancers (CRCs). This was a retrospective study of emergency CRC resection in a tertiary center between March 2016 and November 2018. A total of 46 patients, with a mean age of 51 years, underwent an emergency colectomy for cancer (males, 26 [56.5%]; females, 20 [43.5%]). CME with CVL was performed for all patients. The mean operative time and blood loss were 188 min and 397 mL, respectively. Only five (10.8%) patients presented with burst abdomen, whereas only three (6.5%) presented with anastomotic leakage. The mean length of vascular tie was 8.7 cm, and the mean number of harvested lymph nodes (LNs) was 21.2. Emergency CME with CVL is a safe and feasible technique when performed by a colorectal surgeon and will result in obtaining a superior specimen with a large number of LNs.

Right colon cancer: The influence of specific location on recurrence and survival

AIM

This study aimed to investigate whether the site of the tumour within the right colon affects survival in patients who underwent right colectomy for colon cancer.

METHODS

An observational retrospective longitudinal study was performed in patients who underwent right colectomy for non-metastatic, invasive right-sided colon cancer. Patients were categorized into two groups based on tumour location: (i) caecum and ascending colon; (ii) hepatic flexure and proximal transverse colon. Demographic and clinical features were characterized, and a survival analysis was performed.

RESULTS

Of the 198 patients enroled in the study, 134 (67.8%) had caecal or ascending colon cancer and 64 (32.3%) had hepatic flexure or transverse colon cancer. Seventy (35.4%) were female and the mean age at the time of surgery was 71.6 (SD 11.4). The groups were comparable with respect to the number of lymph nodes sampled, the pTNM stage, the histological differentiation grade and the likelihood of patients receiving adjuvant chemotherapy. Recurrence rate was nearly twice as high in the hepatic flexure and proximal transverse colon group (12.5% vs 6.7%), but this difference was not statistically significant (p = 0.174). Kaplan-Meier analysis showed no differences in disease-free (p = 0.255) and overall survival (p = 0.258) between the groups.

CONCLUSION

In our population, specific location of right-sided colon cancers does not appear to have an influence on survival. Further investigation is needed to determine if tumour subsite has an impact on the recurrence rate, and whether it should be considered in defining prognosis and treatment.

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.

Central vascular ligation and mesentery based abdominal surgery

In the nineteenth century the idea of a correct surgical approach in oncologic surgery moved towards a good lymphadenectomy. In colon cancer the segment is removed with adjacent mesentery, in gastric cancer or pancreatic cancer a good oncologic resection is obtained with adequate lymphadenectomy. Many guidelines propose a minimal lymph node count that the surgeon must obtain. Therefore, it is essential to understand the adequate extent of lymphadenectomy to be performed in cancer surgery. In this review of the current literature, the focus is on "central vascular ligation", understood as radical lymphadenectomy in upper and lower gastrointestinal cancer, the evolution of this approach during the years and the improvement of laparoscopic techniques. For what concerns laparoscopic surgery, the main goal is to minimize post-operative trauma introducing the "less is more" concept whilst preserving attention for oncological outcomes. This review will demonstrate the importance of a scientifically based standardization of oncologic gastrointestinal surgery, especially in relation to the expansion of minimally invasive surgery and underlines the importance to further investigate through new randomized trials the role of extended lymphadenectomy in the new era of a multimodal approach, and most importantly, an era where minimally invasive techniques and the idea of "less is more" are becoming the standard thought for the surgical approach.

D3-lymphadenectomy enhances oncological clearance in patients with right colon cancer. Results of a meta-analysis

BACKGROUND

D3-Lymphadenectomy, together with complete mesocolic excision (CME), were introduced to provide oncological results after right colon cancer. The aim of this systematic review with meta-analysis was to assess the short and long-term outcomes of right-sided hemicolectomy with CME + D3 as compared with classic right hemicolectomy. Secondary aims included the prevalence of D3-metastasis and skip metastasis when performing CME + D3.

MATERIAL AND METHODS

A systematic review with meta-analysis was conducted, according to PRISMA methodology.

RESULTS

29 studies were enrolled (2592 patients). No differences were accounted in morbidity variables associated with the measured techniques. CME + D3 was significantly associated with a greater distance between the tumour and the closest vascular tie, a longer colonic resection, a wider resection of mesentery and an increased number of harvested lymph nodes. Regarding to long-terms outcomes, we found a significant decrease in local recurrence in patients undergoing CME + D3 (HR:0.17) and a significant improvement in 3-year and 5-year overall survival rates (HR:0.53 vs. HR:0.57, respectively), as well as an improving survival in patients with stage II and III disease. Overall prevalence of patients with lymphatic metastases in D3-territory was of 8.6% and 2.2% of skip metastases.

CONCLUSIONS

CME + D3 is a feasible surgical procedure that allows to obtain specimens with higher quality oncological resection, without greater associated morbidity, thus improving survival in patients with stage II and III right colon cancer.

Complete mesocolic excision versus conventional surgery for colon cancer: A systematic review and meta-analysis

AIM

Complete mesocolic excision (CME) lacks consistent data advocating operative superiority compared to conventional surgery for colon cancer. We performed a systematic review and meta-analysis, analysing population characteristics and perioperative, pathological and oncological outcomes.

METHODS

D3 extended lymphadenectomy dissection was considered comparable to CME, and D2 and D1 dissection to be comparable to conventional surgery. Outcomes reviewed included lymph node yield, R1 resection, overall complications, overall survival and disease-free survival.

RESULTS

In all, 3039 citations were identified; 148 studies underwent full-text reviews and 31 matched inclusion criteria: total cohort 26 640 patients (13 830 CME/D3 vs. 12 810 conventional). Overall 3- and 5-year survival was higher in the CME/D3 group compared with conventional surgery: relative risk (RR) 0.69 (95% CI 0.51-0.93, P = 0.016) and RR 0.78 (95% CI 0.64-0.95, P = 0.011) respectively. Five-year disease-free survival also demonstrated CME/D3 superiority (RR 0.67, 95% CI 0.52-0.86, P < 0.001), with similar findings at 1 and 3 years. There were no statistically significant differences between the CME/D3 and conventional group in overall complications (RR 1.06, 95% CI 0.97-1.14, P = 0.483) or anastomotic leak (RR 1.02, 95% CI 0.81-1.29, P = 0.647).

CONCLUSIONS

Meta-analysis suggests CME/D3 may have a better overall and disease-free survival compared to conventional surgery, with no difference in perioperative complications. Quality of evidence regarding survival is low, and randomized control trials are required to strengthen the evidence base.

Complete Mesocolic Excision and D3 Lymphadenectomy versus Conventional Colectomy for Colon Cancer: A Systematic Review and Meta-Analysis

BACKGROUNDS

Previous systematic reviews suggest that the implementation of 'complete mesocolon excision' (CME) for colon tumors entails better specimen quality but with limited long-term outcomes. We performed a meta-analysis to compare the pathological, perioperative, and oncological results of CME with conventional surgery (CS) in primary colon cancer.

METHODS

Embase, MEDLINE and CENTRAL databases were searched using Medical Subject Headings for CME and D3 lymphadenectomy. The systematic review was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines.

RESULTS

A total of 18,989 patients from 27 studies were included. Postoperative complications were higher in the CME group (relative risk [RR] 1.13, 95% confidence interval [CI] 1.04-1.22, I² = 0%), while no differences were observed in terms of anastomotic leak (I² = 0%) or perioperative mortality (I² = 49%). CME was associated with a higher number of lymph nodes harvested (I² = 95%), distance to high tie (I² = 65%), bowel length (I² = 0%), and mesentery area (I² = 95%). CME also had positive effects on 3- and 5-year overall survival (RR 1.09, 95% CI 1.04-1.15, I² = 88%; and RR 1.05, 95% CI 1.02-1.08, I² = 62%, respectively) and 3-year disease-free survival (RR 1.10, 95% CI 1.04-1.17, I² = 22%), as well as decreased local (RR 0.35, 95% CI 0.24-0.51, I² = 51%) and distant recurrences (RR 0.71, 95% CI 0.60-0.85, I² = 34%).

CONCLUSIONS

Limited evidence suggests that CME improves oncological outcomes with a higher postoperative adverse events rate but no increase in anastomotic leak rate or perioperative mortality, compared with CS.

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 Prognostic Significance of Lymph Node Status and Lymph Node Ratio (LNR) on Survival of Right Colon Cancer Patients: a Tertiary Center Experience

BACKGROUND

Colon cancer is a major health problem and is one of the most frequent cancers all over the world. In Egypt, the incidence of colon cancer is relatively low, but its mortality rate is high. Lymphatic spread of colon cancer is one of the most important factors affecting the prognosis of patients. Recently, the lymph node ratio (LNR) has been evaluated as a prognostic parameter for survival. This study aimed at evaluation of nodal status of resected specimens and LNR, as well as its impact on the disease-free survival (DFS) and overall survival (OS) after curative resection of right colon cancer.

METHODS

The institutional registry of the Oncology Center Mansoura University (OCMU) was revised for node-positive right colon cancer cases that were operated in the period between January 2010 and January 2015. Fifty-three patients met the inclusion criteria and were followed up till January 2020.

RESULTS

A total of 766 lymph nodes were excised from the patients. Thirty-two patients (60.4%) had a LN yield of ≥12 LNs with a mean LNR of 0.257 ± 0.27. Multivariate analysis of outcomes showed that LNR was significantly correlated with both DFS (p = 0.015) and OS (p = 0.024). Moreover, the number of resected LNs was also associated with statistically significant relationship with the DFS and OS.

CONCLUSION

Our study confirms the validity of LNR as a prognostic tool that correlates with the survival of patients. Moreover, LNR cutoff values may help predict those of high chance of tumor recurrence.

TRIAL REGISTRATION

MS/20.03.1087 (Institutional IRB), date of registration: March 10, 2020, "retrospectively registered".