A Randomized Phase III Trial of Complete Mesocolic Excision Compared with Conventional Surgery for Right Colon Cancer: Interim Analysis of a Nationwide Multicenter Study of the Italian Society of Surgical Oncology Colorectal Cancer Network (CoME-in trial)

BACKGROUND

Although complete mesocolic excision (CME) is supposed to be associated with a higher lymph node (LN) yield, decreased local recurrence, and survival improvement, its implementation currently is debated because the evidence level of these data is rather low and still not supported by randomized controlled trials.

METHOD

This is a multicenter, randomized, superiority trial (NCT04871399). The 3-year disease-free survival (DFS) was the primary end point of the study. The secondary end points were safety (duration of operation, perioperative complications, hospital length of stay), oncologic outcomes (number of LNs retrieved, 3- and 5-year overall survival, 5-year DFS), and surgery quality (specimen length, area and integrity rate of mesentery, length of ileocolic and middle-colic vessels). The trial design required the LN yield to be higher in the CME group at interim analysis.

RESULTS

Interim data analysis is presented in this report. The study enrolled 258 patients in nine referral centers. The number of LNs retrieved was significantly higher after CME (25 vs. 20; p = 0.012). No differences were observed with respect to intra- or post-operative complications, postoperative mortality, or duration of surgery. The hospital stay was even shorter after CME (p = 0.039). Quality of surgery indicators were higher in the CME arm of the study. Survival data still were not available.

CONCLUSIONS

Interim data show that CME for right colon cancer in referral centers is safe and feasible and does not increase perioperative complications. The study documented with evidence that quality of surgery and LN yield are higher after CME, and this is essential for continuation of patient recruitment and implementation of an optimal comparison. Trial registration The trial was registered at ClinicalTrials.gov with the code NCT04871399 and with the acronym CoME-In trial.

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.

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.

Complete mesocolic excision and central vascular ligation in colorectal cancer in the era of minimally invasive surgery

Since the 19^th century, appropriate lymphadenectomy has been considered a cornerstone of oncologic surgery and one of the most important prognostic factors. This approach can be applied to any surgery for gastrointestinal cancer. During surgery for colon and rectal cancer, an adequate portion of the mesentery is removed together with the segment of bowel affected by the disease. The adequate number of lymph nodes to be removed is standardized and reported by several guidelines. It is mandatory to determine the appropriate extent of lymphadenectomy and to balance its oncological benefits with the increased morbidity associated with its execution in cancer patients. Our review focuses on the concept of “complete mesenteric excision (CME) with central vascular ligation (CVL),” a radical lymphadenectomy for colorectal cancer that has gained increasing interest in recent years. The aim of this study was to evaluate the evolution of this approach over the years, its potential oncologic benefits and potential risks, and the improvements offered by laparoscopic techniques. Theoretical advantages of CME are improved local-relapse rates due to complete removal of the intact mesocolic fascia and improved distance recurrence rates due to ligation of vessels at their origin (CVL) which guarantees removal of a larger number of lymph nodes. The development and worldwide diffusion of laparoscopic techniques minimized postoperative trauma in oncologic surgery, providing the same oncologic results as open surgery. This has been widely applied to colorectal cancer surgery; however, CME entails a technical complexity that can limit its wide minimally-invasive application. This review analyzes results of these procedures in terms of oncological outcomes, technical feasibility and complexity, especially within the context of minimally invasive surgery.

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.

Modified complete mesocolic excision with central vascular ligation by the squeezing approach in laparoscopic right colectomy

PURPOSE

Complete mesocolic excision (CME) and central vascular ligation (CVL) are becoming the standard procedure in laparoscopic right-sided colectomy. However, the approach to CME and CVL has not been established, although several useful approaches have been reported. The squeezing approach described herein is a novel procedure to perform modified CME and CVL in laparoscopic right colectomy.

METHODS

The squeezing approach features retroperitoneal mobilization followed by cranial mesocolic mobilization and lymph node dissection using a cranial approach followed by a caudal approach. Dissection of the regional lymph nodes along with central vascular ligation was performed along the anterior wall of the superior mesenteric vein. In total, 177 patients (mean age, 70.6 years; male-to-female ratio, 90:87) who underwent laparoscopic right-sided colectomy were retrospectively assessed. Descriptive statistics for patient characteristics were calculated.

RESULTS

The mean operative time and blood loss were 169 min and 37 mL, respectively. Seven patients (4.0%) required conversion to open surgery, and major postoperative complications occurred in five patients (2.8%) with no anastomotic leakage. Histological R0 resection was achieved in all cases of stages 0-III colon cancer. The 5-year recurrence-free survival rates were 100% (n = 19), 100% (n = 40), 87% (n = 46), and 81% (n = 43) in pathological stages 0, I, II, and III, respectively. Node recurrence occurred in one case near the root of the middle colic artery.

CONCLUSION

The novel squeezing approach in laparoscopic right colectomy could be safely performed in terms of the technical and oncological aspects.

Predictive value of computed tomography with coronal reconstruction in right hemicolectomy with complete mesocolic excision for right colon cancers: a retrospective study

Background

Understanding the vascular anatomy is critical for performing central vascular ligation (CVL) in right hemicolectomy with complete mesocolic excision (CME). This study aimed to investigate the predictive value of multi-slice spiral computed tomography (MSCT) with coronal reconstruction in right hemicolectomy with CME.

Methods

This is a retrospective descriptive study. Eighty patients with right colon cancer who underwent right hemicolectomy from December 2015 to January 2020 were included. The intraoperative reports (including imaging data) and MSCT images with coronal reconstruction were analysed and compared. The detection rates of the ileocolic vein (ICV) and ileocolic artery (ICA) roots and the accuracy in predicting their anatomical relationship were analysed. The detection rate and accuracy in predicting the location of the gastrocolic trunk of Henle (GTH), middle colic artery (MCA) and middle colic vein (MCV) were analysed. The distance from the ICV root to the GTH root (ICV-GTH distance) was measured and analysed. The maximum distance from the left side of the superior mesenteric artery (SMA) to the right side of the superior mesenteric vein (SMV), named the ‘lsSMA-rsSMV distance’, was also measured and analysed.

Results

In seventy-four (92.5%) patients, both the ICV and ICA roots were located; their anatomical relationship was determined by MSCT, and the accuracy of the prediction was 97.2% (72/74). The GTH was located by MSCT in 75 (93.7%) patients, and the accuracy of the prediction was 97.33% (73/75). The MCA was located by MSCT in 47 (58.75%) patients, and the accuracy was 78.72% (37/47). The MCV was located by MSCT in 51 (63.75%) patients, and the accuracy of the prediction was 84.31% (43/51). The ICV-GTH distance was measured in 73 (91.2%) patients, and the mean distance was 4.28 ± 2.5 cm. The lsSMA-rsSMV distance was measured in 76 (95%) patients, and the mean distance was 2.21 ± 0.6 cm.

Conclusions

With its satisfactory accuracy in predicting and visualising the information of key anatomical sites, MSCT with coronary reconstruction has some predictive value in CME with CVL in right hemicolectomy.

The use of ultrasound in central vascular ligation during laparoscopic right-sided colon cancer surgery: technical notes

BACKGROUND

Complete mesocolic excision (CME) with central vascular ligation (CVL) requires the surgeon to sharply dissect the mesocolon and approach the superior mesenteric artery (SMA) and superior mesenteric vein (SMV) for ligation of the supplying vessels relating to right-sided colon cancer at their origin. Even with preoperative images, it can still be challenging to identify these structures during laparoscopic surgery because of various intraoperative conditions. The aim of this study was to assess the efficacy of intraoperative ultrasound (IOUS) for identification of blood vessels during right-sided colon cancer surgery.

METHODS

We performed IOUS on 19 patients diagnosed with right-sided colon cancer at our institution, in January-October 2020. Preoperatively, a three-dimensional computed tomography (3D-CT) angiogram was obtained for the majority of patients to visualize the SMA, SMV, and their respective branches. The running position of the ileocolic artery (ICA) and right colic artery (RCA) related to the SMV and the presence of the middle colic artery were identified and compared using preoperative 3D-CT, IOUS, and intraoperative findings.

RESULTS

Nineteen patients [seven men and 12 women with a mean age of 73.9 ± 8.4 years (range 58-82 years)] were studied, including some with a body mass index of > 30 kg/m², locally advanced cancer, and severe adhesion. There were IOUSs that detected the SMA, SMV, and their tributaries in all patients. The positional relationships between the SMV and the ICA and RCA revealed by IOUS were consistent with the preoperative and intraoperative findings.

CONCLUSION

IOUS is a safe, feasible, and reproducible technique that can assist in detecting the branching of the SMA and SMV during CME with CVL in laparoscopic right-sided colon cancer surgery, regardless of individual conditions.

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.

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.

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.

Robotic Complete Mesocolic Excision with Central Vascular Ligation for Right Colon Cancer: Surgical Technique and Short-term Outcomes

BACKGROUND

Minimally invasive colorectal surgery has demonstrated to have the same oncological results as open surgery, with better clinical outcomes. Robotic assistance is an evolution of minimally invasive technique.

PURPOSE

The study aims to present technical details and short-term oncological outcomes of robotic-assisted complete mesocolic excision (CME) with central vascular ligation (CVL) for right colon cancer.

METHODOLOGY

Fifty-two consecutive patients affected by right colon cancer were operated between May 2016 and February 2020 with da Vinci Xi platform. Data regarding surgical and short-term oncological outcomes were systematically collected in a colorectal specific database for statistical analysis.

RESULTS

Thirty-seven (71.15%) and 15 (28.85%) patients underwent right and extended right hemicoletomy with an extracorporeal anastomosis. Median age was 55 years. Mean operative time was 182 ± 36 min. Mean blood loss was 110 ± 90 ml. Conversion rate was 3.84% (two cases). 78.84% (41 cases) were pT3 and mean number of harvested lymph nodes was 28 ± 4. 1/52 (1.92%) had a documented anastomotic leak requiring exploratory laparotomy and diversion proximal ileostomy. Surgery-related grade IIIa-IIIb Calvien Dindo morbidity were noted in 9.61% and 1.92%, respectively.

CONCLUSION

Robotic assistance allows performance of oncological adequate dissection of the right colon with radical lymphadenectomy as in open surgery, confirming the safety and oncological adequacy of this technique, with acceptable results and short-term outcomes.

Optimal extent of central lymphadenectomy for right-sided colon cancers: is lymphadenectomy beyond the superior mesenteric vein meaningful?

PURPOSE

The objective of the current study was to assess the therapeutic benefit of lymphadenectomy according to the extent of lymphadenectomy.

METHODS

Patients undergoing colectomy for right-sided colon cancer were identified. Distribution of lymph node metastases (DLNM) of 1, 2 and 3 were defined as lymph node metastasis (LNM) in the pericolic nodes, the intermediate nodes and the front of the SMV near the origin of the major artery, respectively. The therapeutic index (TI) was calculated based on the frequency of LNM and the 5 year overall survival (OS) rate of patients with LNM.

RESULTS

Among 344 patients who met the inclusion criteria, roughly half had LNM (n = 150, 43.7%). While 107 (31.1%) and 30 (8.7%) patients had DLNM1 and DLNM2, respectively, only 13 patients (3.8%) were defined as DLNM3. However, there was no significant difference in 5 year OS by DLNM (DLNM1 71.1%, DLNM2 78.7%, DLNM3 50.4%, p = 0.61). Overall, the TI of lymphadenectomy for D3 area was approximately 1/10 of the TI for D1 (1.9 vs.22.1), given the low frequency of LNM (3.8%) and poor 5 year OS of patients with LNM (50.4%). This trend was consistent irrespective of primary tumor locations.

CONCLUSION

The survival benefit from central lymphadenectomy namely D3 was low among patients with right-sided colon cancers.

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.

Post-operative computed tomography scan – reliable tool for quality assessment of complete mesocolic excision

BACKGROUND

Quality control in colon cancer surgery is an ongoing debate ever since standardization proved to be highly efficient in improving survival in rectal cancer. Complete mesocolic excision (CME) is widely acclaimed as the new gold-standard in colon cancer resections, thus it is imperative to establish quality criteria of CME in order to make it easily understood and verified by surgeons worldwide. One simple and reproducible tool could be the measurement of arterial stumps postoperatively and a straightforward way to test its reliability is to test it in a comparative study between CME and non-CME surgery.

AIM

To validate arterial stump measurement as a surgical quality tool by comparing CME with conventional radical colectomies.

METHODS

This was a retrospective study, carried out on a prospective database. We collected data from two groups of patients, divided according to standard CME with D2 central vascular ligation (group A) and non-standardized surgery (group B). The two groups were compared with regard to the arterial stump length after right- and left-sided colectomies for colon cancer. The actual stump lengths of the ileocolic artery (ICA) and inferior mesenteric artery (IMA) were compared with their theoretical best D2 position of predicted ligation levels (D₂PLLs) for calculating the potential for improvement. Measurements on follow-up computed tomography scans were carried out by three observers. Pathological data were recorded (specimen length, lymph node yield) and correlated with stump length.

RESULTS

We analysed 58 colectomies. The stump lengths (mean ± SD) in group A were 16.97 ± 4.77 mm for ICA and 31.70 ± 15.71 mm for IMA, whereas group B had 49.93 ± 20.29 mm for ICA and 67.24 ± 28.71 mm for IMA. Shorter lengths were obtained in group A, by a mean difference of 35.66 mm (χ² = 27.38, P < 0.001), which was significant for all types of colectomies. Except for a 5.85 ± 4.71 mm difference for right colectomies, all the ligations from group A significantly reached their potential height (0.26 ± 12.18 mm from D₂PLL; χ² = 0.005, P = 0.944). Apart from three left colectomies, group B failed to reach D₂PLL, by a mean difference of 32.14 ± 26.15 mm (χ² = 21.77, P < 0.001). The calculated improvement potentials were significantly shorter in group A than in group B, by a mean of 31.88 mm (χ²= 22.13, P < 0.001). The large spread of results in group B showed that there is significant variability (P = 0.004) when compared to standard surgery. Significant correlations were found between stump length, specimen length and number of lymph nodes (P = 0.018 and P = 0.008 respectively). No statistical difference was found between observers’ measurements (P = 0.866).

CONCLUSION

Arterial stump monitoring is a significant step in defining surgical quality, as longer stumps contain residual mesocolic tissue and correlate with major prognostic factors.

Comparison between conventional colectomy and complete mesocolic excision for colon cancer: a systematic review and pooled analysis : A review of CME versus conventional colectomies

BACKGROUND

Complete mesocolic excision (CME) is advocated based on oncologic superiority, but not commonly performed in North America. Many data are case series with few comparative studies. Our aim was to perform a systematic review comparing outcomes between CME and non-CME colectomy.

METHODS

A systematic review was performed according to PRISMA guidelines of MEDLINE, EMBASE, HealthStar, Web of Science, and Cochrane Library. Studies were included if they compared conventional resection (non-CME) to CME for colon cancer. Quality was assessed using methodological index for non-randomized studies (MINORS). The main outcome measures were short-term morbidity and oncologic outcomes. Weighted pooled means and proportions with 95% CI were calculated using a random-effects model when appropriate.

RESULTS

Out of 825 unique citations, 23 studies underwent full-text reviews and 14 met inclusion criteria. Mean MINORS score was 13.3 (range 11-15). The mean sample size in CME group was 1166 (range 45-3756) and 945 (range 40-3425) in non-CME. Four papers reported plane of dissection, with CME plane achieved in 85.8% (95% CI 79.8-91.7). Mean OR time in CME group was 167 min (163-171) and 138 min (135-142) in conventional group. Perioperative morbidity was reported in six studies, with pooled overall complications of 22.5% (95% CI 18.4-26.6) for CME and 19.6 (95% CI 13.6-25.5) for non-CME. Anastomotic leak occurred in 6.0% (95% CI 2.2-9.7) of CME resections versus 6.0% (95% CI 4.1-7.9) in non-CME. CME had more lymph nodes, longer distance to high tie, and specimen length in all studies. Nine studies compared long-term oncologic outcomes and only three reported statistically significant higher disease-free or overall survival in favor of CME. Local recurrence was lower after CME in two of four studies.

CONCLUSIONS

The quality of evidence is limited and does not consistently support the superiority of CME. Better data are needed before CME can be recommended as the standard of care for colon cancer resections.

Postoperative morbidity of complete mesocolic excision and central vascular ligation in right colectomy: a retrospective comparative cohort study

BACKGROUND

To investigate morbidity and mortality following complete mesocolic excision (CME) and central vascular ligation (CVL) in patients undergoing right colectomy.

METHODS

Data from consecutive patients undergoing elective right colectomy at a university-affiliated referral centre were retrospectively analysed. Patients who underwent conventional right-sided colonic cancer surgery (January 2001-April 2009, n = 84) were compared to patients who underwent CME/CVL (May 2009-January 2015, n = 71). The primary end point was anastomotic leak. Secondary end points were delayed gastric emptying, severe respiratory failure, mortality and length of hospital stay.

RESULTS

No significant difference was found in the rate of anastomotic leak (1.2% in the conventional versus 5.6% in the CME/CVL group, p = 0.108). Patients in the CME/CVL group had a higher 90-day mortality rate (7.0% versus 0.0%, p = 0.019). Four out of five deceased patients suffered from aspiration with consecutive respiratory failure. There was a tendency towards delayed gastric emptying in the CME/CVL group (12.7% versus 7.1%, p = 0.246). Clavien-Dindo complication grades ≥ 2 were similar in both groups with 16 (19%) in the conventional and 15 (21.1%) in the CME/CVL group (p = 0.747). CME/CVL patients had a shorter mean length of stay with 11 versus 14 days (p <  0.001).

CONCLUSIONS

Complete mesocolic excision with central vascular ligation in right colectomy seems to have a higher aspiration rate leading to severe respiratory failure and to higher mortality compared to conventional resection methods. Patient selection for this procedure may therefore be crucial.

How we do it: totally laparoscopic complete mesocolon excision for splenic flexure cancer

BACKGROUND

Splenic flexure (SF) cancer is not a common condition and its treatment is still under discussion. Although laparoscopic surgery is well accepted for the treatment of colon cancer at any stage, complete mesocolon excision (CME) with selective vascular ligation using the laparoscopic approach for SF cancer remains technically demanding and represents a real challenge for surgeons.

METHODS

We present a single-institution experience of laparoscopic CME for SF cancer. Intra-operative, pathologic, and post-operative data of patients who underwent laparoscopic SF resection were reviewed to assess the technical feasibility and oncologic safety. Technical features, histopathology, morbidity, and mortality were evaluated.

RESULTS

From February 2015 to October 2017, a minimally invasive approach was proposed to 17 patients (M/F 14/3) affected by splenic flexure cancer. In all patients, the procedure was completed by laparoscopy. The anastomosis was completed intra-corporeally in 89% of cases. The distal margin was 3.1 ± 2.6 cm and the proximal margin was 6.5 ± 3.3 cm from the tumor site. The number of mean harvested nodes was 13.9 ± 7. The mean operative time was 215.5 ± 65 min, and blood loss was 80 ± 27. In one case, a laparoscopic partial gastrectomy was associated due to tumor invasion. The mean post-operative stay was 6.7 ± 3.3 days. Readmission was necessary for two patients. No major morbidity was recorded.

CONCLUSIONS

Despite the wide spread and increasing confidence in laparoscopic colectomy, SF resection remains one of the most challenging procedures in colorectal surgery with a complex learning curve. SF resection with CME and CVL is feasible and safe for the treatment of early-stage and locally advanced SF cancer.

Surgical and oncological outcomes after complete mesocolic excision in right-sided colon cancer compared with conventional surgery: a retrospective, single-institution study

PURPOSE

The aim of the study was whether complete mesocolic excision (CME) with central vascular ligation (CVL) is associated with a survival benefit compared with traditional procedure in right-sided colon cancer.

METHODS

Overall, 251 consecutive patients underwent surgery for right colon cancer between 2007 and 2012. After exclusion, 95 subjects received non-CME surgery before 2010, and 97 subjects received CME surgery after January 2010, when we started to perform CME systematically. The number of lymph nodes, morbidity, and mortality was analyzed. Overall survival (OS) and disease-specific survival (DSS) were investigated.

RESULTS

The median number of examined lymph nodes was 33.28 in the CME group and 26.92 in the non-CME group, p < 0.001. Postoperative complications were 21.6% in the CME group and 17.8% in the non-CME group, without significant difference. One out of 192 patients died. Three-year OS was 88% in the CME group and 71% in the non-CME group (p = 0.003). In stage II, 3-year DSS was 97% in the CME group and 86% in the non-CME group. In stage III, the 3-year DSSs in the CME and in the non-CME groups were 86 and 67%, respectively (p < 0.001). Cox's regression showed that CME (p = 0.0012), the number of lymph nodes (p = 0.029), and TNM stage (p < 0.001) were significant independent predictors of DSS at 3 years.

CONCLUSION

Surgical standardization of CME with CVL for right-sided colon cancer is associated with better staging and prognosis, particularly in UICC stage II and III. This study shows that CME is safe and reproducible with acceptable morbidity.

Laparoscopic vs open complete mesocolic excision with central vascular ligation for colon cancer: A systematic review and meta-analysis

AIM

To compare the effectiveness of laparoscopic complete mesocolic excision (CME) with central vascular ligation (L-CME) with its open (O-CME) counterpart.

METHODS

We conducted an electronic search of the PubMed/MEDLINE, Excerpta Medica Database, Web of Science Core Collection, Cochrane Center Register of Controlled Trails, Cochrane Database of Systematic Reviews, SciELO, and Korean Journal databases from their inception until May 2017. We considered randomized controlled trials (RCTs) and controlled clinical trials (CCTs) that included patients with colonic cancer comparing L-CME and O-CME. Primary outcomes included the quality of the resected specimen (lymph nodes retrieved, complete mesocolic plane excision, tumor to arterial high tie, resected mesocolon surface). Secondary outcomes included the three-year and five-year overall and disease-free survival rates, recurrence of the disease, surgical data, and postoperative morbidity and mortality. Two authors of the review screened the methodological quality of the eligible trials and independently extracted data from individual studies.

RESULTS

A total of one RCT and eleven CCTs (four from Europe and seven from Asia) met the inclusion criteria for the current meta-analysis. These studies involved 1619 patients in L-CME and 1477 patients in O-CME. The L-CME was associated with the same quality of the resected specimen, with no differences regarding the retrieved lymphnodes (MD = -1.06, 95%CI: -3.65 to 1.53, P = 0.42), and tumor to high tie distance (MD = 14.26 cm, 95%CI: -4.30 to 32.82, P = 0.13); the surface of the resected mesocolon was higher in the L-CME group (MD = 11.75 cm², 95%CI: 9.50 to 13.99, P < 0.001). The L-CME was associated with a lower rate of blood transfusions (OR = 0.45, 95%CI: 0.27 to 0.75, P = 0.002), faster recovery of gastrointestinal function, and less postoperative overall complication rate. The L-CME approach was associated with a statistical significant better three-year overall (OR = 2.02, 95%CI: 1.31 to 3.12, P = 0.001, I² = 28%) and disease-free (OR = 1.45, 95% CI: 1.00 to 2.10, P = 0.05, I² = 0%) survival.

CONCLUSION

The laparoscopic approach offers the same quality of the resected specimen as the open approach in complete mesocolic excision with central vascular ligation for colon cancer. The laparoscopic complete mesocolic excision with central vascular ligation is superior in all perioperative results and at least non-inferior in long-term oncological outcomes.

Laparoscopic complete mesocolic excision with central vascular ligation in 600 right total mesocolectomies: Safety, prognostic factors and oncologic outcome

BACKGROUND

To analyze our experience with laparoscopic right Mesocolectomy in right colonic cancers.

METHODS

600 consecutive patients were studied.

RESULTS

Mortality was 0.5%; morbidity was 35.5%. Mean mesocolic area was 15339 ± 1639 mm3, specimen length 24.3 ± 3.3 cm, distance from the tumor to high tie was 103 ± 6 mm and mean lymph nodes harvested was 27 ± 3; mesocolic plane was achieved in 81% of cases. Survival was 83%; stratified survival in patients with stage II, IIIA/B and in the subgroup of stage IIIC patients with negative apical nodes was 88.7%, 72.4%, 71.4% respectively; stage IIIC patients with positive apical nodes showed poor survival (27.7%). Recurrence occurred in 177 patients (29.5%) and was mainly systemic (22.7%). At the multivariate analysis, "non mesocolic" plane of resection, positive N3 apical nodes and CEA levels >5 ng/dL were found to be independent prognostic factors.

CONCLUSIONS

Laparoscopic right Mesocolectomy showed to be safe and yielded surgical specimens of high quality, with impact on survival; positive N3 apical nodes and "non mesocolic" planes were independently associated to poor outcome.

Surgery along the embryological planes for colon cancer: a systematic review of complete mesocolic excision

BACKGROUND

Complete mesocolic excision (CME) for colonic cancer offers a surgical specimen of higher quality, with higher number of lymph nodes compared to conventional colectomy. However, evidence on oncological outcomes is limited. The aim of the present study is to review recent literature and provide more information regarding the effect of CME colectomy on short- and long-term outcomes.

METHOD

PubMed and MEDLINE databases were searched, and articles in English reporting data on CME were reviewed. Intraoperative events; postoperative morbidity and mortality; histopathological characteristics, including macroscopic assessment, number, and status of retrieved lymph nodes; and oncological outcomes were the end-points.

RESULTS

Thirty-two studies were analyzed. As regards the macroscopic assessment, a larger specimen (p = 0.02) that contains a higher number of lymph nodes (p < 0.00001) is acquired after CME. Two studies report a higher disease-free survival, in stage I and II and particularly in stage III disease after CME. CME by laparoscopy offers comparable outcomes, as regards intraoperative blood loss and immediate postoperative morbidity and mortality rates. Specimen quality is similar after either approach, for cancers located at the right and left colon, but not at the transverse colon.

CONCLUSION

There is strong evidence that CME offers a longer central pedicle that contains more lymph nodes than conventional surgery for colon cancer. CME represents the surgical background for the maximum lymph node harvest, an important quality marker for the surgical outcome. However, and according to present data, there is limited evidence that colectomy in terms of CME leads to improved long-term oncological outcomes.

Laparoscopic complete mesocolic excision with central vascular ligation in right colon cancer: A comprehensive review

Aim of the study is to comprehensively review the latest trends in laparoscopic complete mesocolic excision (CME) with central vascular ligation (CVL) for the multimodal management of right colon cancer. Historical and up-to-date anatomo-embryological concepts are analyzed in detail, focusing on the latest studies of the mesenteric organ, its dissection by mesofascial and retrofascial cleavage planes, and questioning the need for a new terminology in colonic resections. The rationale behind Laparoscopic CME with CVL is thoroughly investigated and explained. Attention is paid to the current surgical techniques and the quality of the surgical specimen, yielded through mesocolic, intramesocolic and muscularis propria plane of surgery. We evaluate the impact on long term oncologic outcome in terms of local recurrence, overall and disease-free survival, according to the plane of resection achieved. Conclusions are drawn on the basis of the available evidence, which suggests a pivotal role of laparoscopic CME with CVL in the multimodal management of right sided colonic cancer: performed in the right mesocolic plane of resection, laparoscopic CME with CVL demonstrates better oncologic results when compared to standard non-mesocolic planes of surgery, with all the advantages of laparoscopic techniques, both in faster recovery and better immunological response. The importance of minimally invasive meso-resectional surgery is thus stressed and highlighted as the new frontier for a modern laparoscopic total right mesocolectomy.