Complete mesocolic excision for right colonic cancer: prospective multicentre study

Central vascular ligation and complete mesocolon excision vs D3 lymphadenectomy: Standardization of surgical technique

Surgical advancements have transformed colorectal cancer treatment, with complete mesocolic excision (CME) becoming a crucial method to guarantee oncological safety and effectiveness. The article by Yadav emphasized the significance of CME in attaining optimal resection margins, thorough lymph node dissection, and enhanced long-term survival rates. The adjunctive function of D3 lymphadenectomy, emphasizing the clearance of lymphatic drainage along the supplying vessels, was also addressed. CME with central vascular ligation, based on the principles of total mesorectal excision for rectal cancer, entails en bloc tumor resection and precise dissection along the embryological planes, thus diminishing recurrence and improving survival rates. The viability and safety of minimally invasive techniques, such as laparoscopic CME, have been confirmed; however, technical difficulties remain owing to the intricate vascular anatomy. Robotic-assisted surgery presents potential benefits, including accurate lymphatic dissection and intracorporeal anastomosis. However, evidence demonstrating its superiority over laparoscopic techniques is scarce owing to high costs and prolonged duration. This study promotes the global standardization of CME as an essential element of modern colorectal cancer surgery. CME epitomizes contemporary oncological practices, requiring widespread adoption to achieve superiority in colon cancer management.

Predicting disease-free survival following curative-intent resection of right-sided colon cancer using a pre- and post-operative nomogram: a prospective observational cohort study

INTRODUCTION

Disease prognostication can be achieved through the derivation of biologically and clinically integrated prediction models. The present study reports 1-, 3-, and 5-year disease-free survival (DFS) in patients undergoing right hemicolectomy for curative intent and both derives and validates a pre- and post-operative prediction tool for DFS for prognostication and risk stratification purposes.

METHOD

Consecutive patients undergoing right-sided curative-intent resection for colorectal cancer (2010-2020) in a tertiary care unit were followed-up prospectively for recurrence and survival outcomes. Survival analyses were used to derive pre- and post-operative models predicting 1-, 3-, and 5-year DFS. Calibration was reported and internal validation was performed using bootstrapping.

RESULTS

A total of 822 patients underwent resection and 528 had ≥5-year follow-up. The 1-, 3-, and 5-year DFS rates were 85.6%, 72.5% and 57.6%, respectively. Variables associated with death/recurrence included: increasing age (HR > 1.95, P = 0.037), male gender (HR 1.62, P < 0.001), ASA ≥3 (HR 1.79, P < 0.001), low albumin (HR 1.54, P < 0.001), T4 stage (HR 2.35, P = 0.023), R1 status (HR 1.63, P = 0.024), ≥4 positive lymph nodes (HR > 1.74, P < 0.001) and Clavien-Dindo ≥3 (HR 2.83, P < 0.001). The pre- and post-operative models contained 9 and 13 demographic, clinical, biochemical, operative and pathological variables, respectively (C-index 0.75 and 0.79, respectively). Excluding demographic, clinical and operative variables significantly reduced the C-index of the pre- (0.62) and post-operative models (0.70).

CONCLUSION

The presented prediction tools for DFS will help clinicians stratify risk, offer appropriate adjuvant treatment and predict long-term DFS following curative-intent right-sided colon cancer resection.

[Evidence for the extent and oncological benefits of lymphadenectomy in colon and rectal cancer : A narrative review based on meta-analyses]

BACKGROUND

Lymphadenectomy for rectal cancer is clearly defined by total mesorectal excision (TME). The analogous surgical strategy for the colon, the complete mesocolic excision (CME), follows the same principles of dissection in embryologically predefined planes.

METHOD

This narrative review initially identified key issues related to lymphadenectomy of rectal and colon cancer. The subsequent search was based on PubMed and focused on meta-analyses. The endpoints for rectal cancer were the benefit of high tie versus low tie and the indications for lateral pelvic lymphadenectomy. For colon cancer the evidence for CME, for the longitudinal extent of resection, for the dissection of infrapyloric and gastroepiploic lymph nodes, for the number of lymph nodes and for the sentinel lymph node technique were used as endpoints.

RESULTS

An oncological benefit of the high tie cannot be derived from the current data. Lateral pelvic lymphadenectomy should only be selectively performed after chemoradiotherapy (CRT) in cases of remaining lymph nodes with suspected metastases. In most studies CME proved to be oncologically superior, especially in stage III. The longitudinal extent of resection should be at least 10 cm in both directions if the principles of CME are observed. Infrapyloric and gastroepiploic lymph node involvement is to be expected in 0.7-22% of cases, depending on patient selection, which justifies dissection, particularly in carcinomas of both flexure and the transverse colon. The minimum number of lymph nodes to be removed cannot be clearly derived from the available studies. Precisely performed CME and an optimal pathological work-up are important. The sentinel lymph node technique cannot currently be used as a criterion for limiting the extent of resection.

CONCLUSION

Both TME and CME are reliable standards for the lymphadenectomy in colorectal carcinomas. A lymphadenectomy that goes beyond this is reserved for selected cases and is partly the subject of currently ongoing studies.

[Extended Complete Mesocolic Excision in right-sided Colon Cancer - An Overview]

Surgical resection with systematic lymphadenectomy remains the standard of care for non-metastasised colon cancer. After the article of Hohenberger et al. in 2009 describing the surgical technique of complete mesocolic excision (CME), D2 lymphadenectomy has been called into doubt after the finding of a better oncological outcome. However, there has been also a controversial discussion about the oncological value of CME, since intraoperative complications may increase. Additional evidence has been provided in recent years from randomised controlled multicentre studies showing that the reported improved oncological long-term outcome after CME is more than questionable. The reported increased rate of intraoperative (vascular) complications could be not confirmed.

Factor analysis of postsurgical gastroparesis syndrome after right hemicolectomy for colon cancer

The present study aimed to investigate factors influencing postsurgical gastroparesis syndrome (PGS) in patients with right-sided colon cancer. In total, 260 patients who underwent complete mesocolic excision for right-sided colon cancer were included in the present analysis. Among the included patients, 69 underwent open radical right-sided colon resection, 175 underwent laparoscopic radical right-sided colon resection and 16 underwent robot-assisted radical right-sided colon resection. The occurrence of PGS was observed, and both the χ2 test and multivariate regression analysis were conducted to identify influencing factors. Among the 260 patients, 32 experienced PGS, with an incidence rate of 12.3%. Univariate analysis demonstrated that age, perioperative blood glucose levels, self-rated anxiety scale scores and surgical approach were significantly associated with PGS (P<0.05), whereas sex, surgical duration, diabetes and perioperative albumin levels were not significant factors (P>0.05). Multivariate logistic regression analysis showed that age >70 years, perioperative blood glucose ≥11.1 mmol/l, a self-rating anxiety scale score ≥50 and radical extended right-sided colon resection were risk factors for PGS occurrence. In conclusion, the occurrence of PGS in patients with right-sided colon cancer was revealed to be associated with age, perioperative blood glucose levels, self-rated anxiety scale scores and surgical approach.

European multicentre analysis of the implementation of robotic complete mesocolic excision for right-sided colon tumours

AIM

Complete mesocolic excision (CME) is an oncologically driven technique for treating right colon cancer. While laparoscopic CME is technically demanding and has been associated with more complications, the robotic approach might reduce morbidity. The aim of this study was to assess the safety of stepwise implementation of robotic CME.

METHOD

A multicentre retrospective analysis of prospectively collected data on robotic right colectomy was performed at five European tertiary centres. Patients were classified for type of surgery: R-RHC (standard right colectomy), R-impCME (learning cases towards robotic CME defined as R-RHC with one but not all the hallmarks of CME) or R-CME (robotic CME). Primary outcomes were overall and severe 30-day complication rates before and after propensity score matching (PSM) analysis.

RESULTS

Five hundred and fifty-one consecutive patients undergoing robotic surgery for (pre)malignant lesions of the right colon between 2010 and 2020 were included: R-RHC (n = 101), R-impCME (n = 135) and R-CME (n = 315). Baseline characteristics differed for American Society of Anesthesiologists score (p = 0.0012) and preoperative diagnosis of adenocarcinoma (p < 0.001). Procedure time increased by surgical complexity (p < 0.001). Vascular event rates did not differ, with no superior mesenteric vein injuries. Conversion, complication and anastomotic leak rates, time to flatus/soft diet and length of stay (LOS) did not differ. While R-RHC was performed for a lower rate of malignancies (p < 0.001), lymph node yield was significantly higher in R-CME (p < 0.001). After PSM, analyses on 186 patients documented no differences in overall and severe 30-day complication rate, conversion rate, LOS or 30-day mortality.

CONCLUSION

R-CME can be implemented without increasing the overall or 30-day severe complication rate.

Laparoscopic right hemicolectomy with complete mesocolon excision and cranial approach

BACKGROUND

Complete mesocolon excision (CME) and D3-lymphadenectomy concepts have gained popularity for the surgical treatment of right colon cancer in comparison to the conventional laparoscopic right hemicolectomy (CLRH). The rationale of CME is to dissect the embryological planes between the mesenteric plane and the parietal fascia to remove the mesentery within a complete envelope of mesenteric fascia and visceral peritoneum that contains lymph nodes, the central vascular ligation, and adequate bowel length to remove involved pericolic lymph nodes in the longitudinal direction, having as the main goal to improve the oncological results. CME with D3-lymphadenectomy is challenge since involves the excision of the lymph adipose tissue covering the medial edge of the superior mesenteric vein (SMV) (trunk of Gillot, TG), and the gastrocolic trunk of Henle (GTH). We describe a LRH with CME using a cranial approach allowing an easier central vessels origin identification.

TECHNIQUE

Through the supramesocolic approach, gastrocolic ligament is opened and the GTH and the middle colic artery (MCA) and vein (MCV) origins are identified. Hepatic flexure is mobilized, and a gauze is placed above the mesenteric vessels. Then, the SMV is identified, dividing the ileocolic vessels origin. The plane between the Gerota and Toldt fascias is opened, identifying duodenum, pancreas, and the gauze previously placed. Following this plane and the SMV along the TG, the GTH and its branches are identified. The superior right colic vein, and the MCA and MCV right branches are divided. After that, colon is fully mobilized laterally opening the parietocolic gutter and an intracorporeal anastomosis is performed.

CONCLUSION

CME could lead to an improvement of oncological results due to a wider mesocolic excision in comparison to conventional D2-lymphadenectomy. Cranial approach facilitates the vessels origin identification to perform a true central ligation.

Complete mesocolic excision (CME) impacts survival only for Stage III right-sided colon cancer: a systematic review and meta-analysis

INTRODUCTION

Complete mesocolic excision (CME) is widely adopted for its assumed superior oncological outcome. However, it's unclear if all right-sided colon cancer patients benefit from CME. The aim of this systematic review is to investigate whether CME contributes to postoperative outcomes and to determine the surgical indications for CME.

MATERIAL AND METHODS

We searched eligible articles about CME versus non-CME procedures for right-sided colon cancer in the OVID Medline, Embase, and Cochrane CENTRAL databases, and a meta-analysis was conducted.

RESULTS

Twenty-two articles and seven abstracts involving 8088 patients were included in this study. Among them, 3803 underwent CME and 4285 non-CME procedures. The analysis showed that CME was favoured for three-year disease-free survival (DFS) and overall survival (OS), for local, systemic, and total recurrence, and for hospital stay durations. However, increased vascular injury and longer surgery time were observed in CME. Regarding the three-year OS, the superiority of CME was observed only in Stage III. Additionally, no significant differences were observed between CME and non-CME groups regarding overall complications, 30-day readmission rates, reoperation, or postoperative mortality rates.

CONCLUSIONS

CME for right-sided colon cancer should be considered, particularly in Stage III patients, to contribute to improved oncological outcomes. However, careful attention must be paid to the increased risk of vascular injury.

Extent of Lymphadenectomy for Surgical Management of Right-Sided Colon Cancer: The Randomized Phase III RELARC Trial

PURPOSE

Complete mesocolic excision (CME) is being increasingly used for the treatment of right-sided colon cancer, although there is still no strong evidence that CME provides better long-term oncological outcomes than D2 dissection. The controversy is mainly regarding the survival benefit from extended lymph node dissection emphasized by CME.

METHODS

This multicenter, open-label, randomized controlled trial (ClinicalTrials.gov identifier: NCT02619942) was performed across 17 hospitals in China. Patients diagnosed with stage T2-T4aNanyM0 or TanyN + M0 right-sided colon cancer were randomly assigned (1:1) to undergo either CME or D2 dissection during laparoscopic right colectomy. The primary outcome was the 3-year disease-free survival (DFS), and the main secondary outcome was the 3-year overall survival (OS).

RESULTS

Between January 11, 2016, and December 26, 2019, 1,072 patients were randomly assigned (536 patients to CME and 536 patients to D2 dissection). In total, 995 patients (median age 61 years, 59% male) were included in the primary analysis (CME [n = 495] v D2 dissection [n = 500]). No significant differences were found between the groups in 3-year DFS (hazard ratio [HR], 0.74 [95% CI, 0.54 to 1.02]; P = .06; 86.1% in the CME group v 81.9% in the D2 group) or in 3-year OS (HR, 0.70 [95% CI, 0.43 to 1.16]; P = .17; 94.7% in the CME group v 92.6% in the D2 group).

CONCLUSION

This trial failed to find evidence of superior DFS outcome for CME compared with standard D2 lymph node dissection in primary surgical excision of right-sided colon cancer. Standard D2 dissection should be the routine procedure for these patients. CME should only be considered in patients with obvious mesocolic lymph node involvement.

Predictors of nodal positivity in clinically under-staged patients with colon cancer: A National Cancer Database study and proposal of a predictive scoring system

BACKGROUND

Colon cancer pathological and clinical staging may be disoncordant. This study assessed patients with colon cancer in whom the nodal status was clinically understaged.

METHODS

Patients with stage I-III clinical node-negative colon cancer from the National Cancer Database were included. Regression analyses were conducted to elucidate risk factors for clinical nodal understaging and a scoring system was developed to identify high-risk patients.

RESULTS

The study included 94,945 patients with 78.4 ​% of patients correctly staged and 21.6 ​% clinically understaged. The predictors of nodal positivity in clinically understaged patients were age <65 (OR 1.43), left-sided tumors (OR 1.41), elevated CEA (OR 2.03), moderately (OR 1.81) or poorly/undifferentiated tumors (OR 3.76), T1 tumors (OR 1.29), signet-ring cell histology (OR 2.26), and microsatellite-stable tumors (OR 1.4).

CONCLUSION

Patients with colon cancer and the above factors are more likely to have their nodal status clinically understaged. A scoring system has been developed to identify high-risk patients.

Proposal for standardization of laparoscopic D3 lymphadenectomy for right colon cancer

BACKGROUND

This study presents a laparoscopic surgical protocol for right hemicolectomy and D3 lymphadenectomy (R-D3L) in right colon cancer and reports the oncological outcomes based on a prospective series.

METHODS

The study comprises two phases. In the first phase, a dynamic demonstration of the R-D3L surgical protocol is provided through textual explanation, illustrations, and edited surgical videos. The protocol emphasizes technical steps such as dissection of the embryological plane of the right mesocolon, high tie of ileocolic vessels, surgical trunk of Gillot dissection, and high tie of superior right colic vein (SRCV). In the second phase, a prospective observational study was conducted involving patients undergoing R-D3L surgery with this protocol between July 2015 and July 2021. Demographic, perioperative, and postoperative variables are analyzed, along with anatomopathological variables and oncological outcomes.

RESULTS

A total of 33 patients were analyzed. Median operative time was 202 min. Perioperative bleeding occurred in 6%. Postoperative complications were mild (Clavien-Dindo III in 2%). Postoperative ileus was observed in 15%. No anastomotic dehiscence was reported. The median postoperative stay was 7 days. The median number of resected lymph nodes was 26, with 27% having positive nodes and 70% were classified as stage T3 or T4. After a median follow-up of 45 months, local recurrence, distant recurrence, and carcinomatosis rates were 0%. Mortality rate from other causes was 9%.

CONCLUSION

The surgical protocol shown in the present study could help in the implementation of this technique in those units that consider it appropriate.

Comparing cranial-caudal-medial and medial-lateral approaches for laparoscopic right hemicolectomy: a propensity score-matched analysis

BACKGROUND

The cranial-caudal-medial approach (CCMA) has been proposed for laparoscopic right hemicolectomy nowadays. This study aimed to investigate the safety and oncological efficacy of CCMA in the treatment of right-sided colon cancer compared to the medial-lateral approach (MLA).

METHODS

Patients diagnosed with right-sided colon cancer were included from February 2015 to June 2018, retrospectively, dividing into the CCMA group and the MLA group. We compared the basic characteristics and the short-term and long-term outcomes in two groups.

RESULTS

Two hundred and ninety-six patients were included in this study. The baseline characteristics were similar in two groups. Compared with MLA group, CCMA group exhibited shorter operation time (136.3 ± 25.3 min vs. 151.6 ± 21.5 min, P < 0.001), lower estimated blood loss (44.1 ± 15.2 ml vs. 51.4 ± 26.9 min, P = 0.010), and more harvested lymph nodes (18.5 ± 7.1 vs. 16.5 ± 5.7, P = 0.021). The 5-year overall survival (OS) rate for the CCMA group was 76.5%, and the 5-year disease-free survival (DFS) rate was 72.3%, both of which were not inferior to the MLA group. No significant difference was found between two groups in terms of other clinical parameters.

CONCLUSION

The CCMA in laparoscopic right hemicolectomy is safe and feasible, making the anatomical plane clearer. This approach can shorten the operation time, reduce intraoperative blood loss, harvest more lymph nodes, and yield satisfactory oncological outcomes.

Surgical treatment of right colon cancer

The study aimed to perform a systematic review of the literature on surgical treatment for right colon cancer (RCC) with complete mesocolic excision (CME) and D2/D3 lymph node dissection (LND). Material and Methods. A literature review was performed for studies published between 2013 and 2023 by the online resources from the official Web sites of the societies/panels and PubMed database. Sources included guidelines, meta-analyses, randomized and nonrandomized clinical studies, guidelines by European Society of Medical Oncology, the Japanese Society for Cancer of the Colon and Rectum, and the National Comprehensive Cancer Network, Russian clinical guidelines. Results. CME significantly improved both immediate and long-term treatment results, which was confirmed by numerous meta-analyses. The extent of LND remains one of the most controversial issues in RCC. For many Asian surgeons, D3 LND is the standard procedure for the treatment of RCC, whereas the European approach is more conservative and apical lymph node dissection is not mandatory. There are also large differences in understanding the extent of D3 LND in RCC. Most surgeons understand this term as dissection of adipose tissue along the anterior and lateral surface of the superior mesenteric vein, however, there are authors who perform circular dissection along the superior mesenteric vessels, considering this extent of surgery to be the most radical. Conclusion. It is necessary to standardize methods and effective criteria for quality control of CME for RCC and LND. In this case, external independent assessment of the quality of surgical intervention is important. There is also currently a growing number of studies in which intraoperative fluorescence imaging makes it possible to better visualize the location of the apical lymph nodes and individualize LND.

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.

Are Metastatic Central Lymph Nodes (D3 volume) in right-sided Colon Cancer a Sign of Systemic Disease? A sub-group Analysis of an Ongoing Multicenter Trial

OBJECTIVE

Assess outcomes of patients with right-sided colon cancer with metastases in the D3 volume after personalized surgery.

BACKGROUND

Patients with central lymph node metastasis (D3-PNG) are considered to have a systemic disease with a poor prognosis. A 3-dimensional definition of the dissection volume allows the removal of all central nodes.

MATERIALS AND METHODS

D3-PNG includes consecutive patients from an ongoing clinical trial. Patients were stratified into residual disease negative (D3-RDN) and residual disease positive (D3-RDP) groups. D3-RDN was further stratified into 4 periods to identify a learning curve. A personalized D3 volume (defined through arterial origins and venous confluences) was removed " en bloc" through medial-to-lateral dissection, and the D3 volume of the specimen was analyzed separately.

RESULTS

D3-PNG contained 42 (26 females, 63.1 SD 9.9 y) patients, D3-RDN:29 (17 females, 63.4 SD 10.1 y), and D3-RDP:13 (9 females, 62.2 SD 9.7 y). The mean overall survival (OS) days were D3-PNG:1230, D3-RDN:1610, and D3-RDP:460. The mean disease-free survival (DFS) was D3-PNG:1023, D3-RDN:1461, and D3-RDP:74 days. The probability of OS/DFS were D3-PNG:52.1%/50.2%, D3-RDN:72.9%/73.1%, D3-RDP: 7.7%/0%. There is a significant change in OS/DFS in the D3-RDN from 2011-2013 to 2020-2022 (both P =0.046) and from 2014-2016 to 2020-2022 ( P =0.028 and P =0.005, respectively).

CONCLUSION

Our results indicate that surgery can achieve survival in most patients with central lymph node metastases by removing a personalized and anatomically defined D3 volume. The extent of mesenterectomy and the quality of surgery are paramount since a learning curve has demonstrated significantly improved survival over time despite the low number of patients. These results imply a place for the centralization of this patient group where feasible.

Effect of complete mesocolic excision (cme) on long-term survival after right colectomy for cancer: multivariate meta-analysis and restricted mean survival time estimation

INTRODUCTION

Debate exists concerning the impact of complete mesocolic excision (CME) on long-term oncological outcomes. The aim of this review was to condense the updated literature and assess the effect of CME on long-term survival after right colectomy for cancer.

METHODS

PubMed, MEDLINE, Scopus, and Web of Science were searched through July 2023. The included studies evaluated the effect of CME on survival. The primary outcome was long-term overall survival. Restricted mean survival time difference (RMSTD), hazard ratio (HR), and 95% confidence intervals (CI) were used as pooled effect size measures. GRADE methodology was used to summarize the certainty of evidence.

RESULTS

Ten studies (3665 patients) were included. Overall, 1443 (39.4%) underwent CME. The RMSTD analysis shows that at 60-month follow-up, stage I-III CME patients lived 2.5 months (95% CI 1.1-4.1) more on average compared with noCME patients. Similarly, stage III patients that underwent CME lived longer compared to noCME patients at 55-month follow-up (6.1 months; 95% CI 3.4-8.5). The time-dependent HRs analysis for CME vs. noCME (stage I-III disease) shows a higher mortality hazard in patients with noCME at 6 months (HR 0.46, 95% CI 0.29-0.71), 12 months (HR 0.57, 95% CI 0.43-0.73), and 24 months (HR 0.73, 95% CI 0.57-0.92) up to 27 months.

CONCLUSIONS

This study suggests that CME is associated with unclear OS benefit in stage I-III disease. Caution is recommended to avoid overestimation of the effect of CME in stage III disease since the marginal benefit of a more extended resection may have been influenced by tumor biology/molecular profile and multimodal adjuvant treatments.

Complete mesocolic excision for colon cancer: current status and controversies

According to Hohenberger's original description, complete mesocolic excision for colon cancer involves precise dissection of the avascular embryonic plane between the parietal retroperitoneum and visceral peritoneum of the mesocolon. This ensures mesocolic integrity, access to high ligation of the supplying vessels at their origin and an associated extended lymphadenectomy. Results from centres which have adopted this approach routinely have demonstrated that oncological outcomes can be improved by the rigorous implementation of established principles of cancer surgery. Meticulous anatomical dissection along embryonic planes is a well-established principle of precision cancer surgery used routinely by the specialist colorectal surgeon. Therefore, the real question concerns the need for true central vascular ligation and associated extended (D3) lymphadenectomy or otherwise, particularly along the superior mesenteric vessels when performing a right colectomy. Whether this approach results in improved overall or disease-free survival remains unclear and its role remains controversial particularly given the potential for significant morbidity associated with a more extensive central vascular dissection. Current literature is limited by considerable bias, as well as inconsistent and variable terminology, and the results of established randomized trials are awaited. As a result of the current state of equipoise, various national guidelines have disparate recommendations as to when complete mesocolic excision should be performed if at all. This article aims to review the rationale for and technical aspects of complete mesocolic excision, summarize available short and long term outcome data and address current controversies.

Nationwide standardization of minimally invasive right hemicolectomy for colon cancer and development and validation of a video-based competency assessment tool (the Right study)

BACKGROUND

Substantial variation exists when performing a minimally invasive right hemicolectomy (MIRH) due to disparities in training, expertise and differences in implementation of innovations. This study aimed to achieve national consensus on an optimal and standardized MIRH technique for colon cancer and to develop and validate a video-based competency assessment tool (CAT) for MIRH.

METHOD

Statements covering all elements of MIRH were formulated. Subsequently, the Delphi technique was used to reach consensus on a standardized MIRH among 76 colorectal surgeons from 43 different centres. A CAT was developed based on the Delphi results. Nine surgeons assessed the same 12 unedited full-length videos using the CAT, allowing evaluation of the intraclass correlation coefficient (ICC).

RESULTS

After three Delphi rounds, consensus (≥80% agreement) was achieved on 23 of the 24 statements. Consensus statements included the use of low intra-abdominal pressure, detailed anatomical outline how to perform complete mesocolic excision with central vascular ligation, the creation of an intracorporeal anastomosis, and specimen extraction through a Pfannenstiel incision using a wound protector. The CAT included seven consecutive steps to measure competency of the MIRH and showed high consistency among surgeons with an overall ICC of 0.923.

CONCLUSION

Nationwide consensus on a standardized and optimized technique of MIRH was reached. The CAT developed showed excellent interrater reliability. These achievements are crucial steps to an ongoing nationwide quality improvement project (the Right study).

[D2 and D3 lymph node dissection for colon cancer]

OBJECTIVE

To evaluate surgical and oncological results of standard and extended lymph node dissection (D2 and D3) in patients with colon cancer.

MATERIAL AND METHODS

We analyzed treatment outcomes in 74 patients with colon cancer stage T1-4aN0-2M0 who underwent right- and left-sided hemicolectomy, resection of sigmoid colon with standard and extended lymph node dissection (D2 and D3).

RESULTS

Surgical approach and level of D3 lymph node dissection did not increase intra- and postoperative morbidity. Laparoscopic interventions were followed by significantly lower intraoperative blood loss and earlier gas discharge. Metastatic lesion of apical lymph nodes was observed in 5 out of 36 patients who underwent D3 lymph node dissection (13.8%), and metastases in regional lymph nodes rN1-2 were found in all these patients. Overall 5-year survival was 86%. Disease-free and overall 5-year survival were similar after D2 and D3 lymph node dissection.

CONCLUSION

D3 lymph node dissection is safe for colon cancer. Metastatic lesions of apical lymph nodes during D3 lymph node dissection were detected only in patients with lesions of regional lymph nodes (rN1-2). Disease-free and overall 5-year survival were similar after D2 and D3 lymph node dissection.

Tata Memorial Centre Evidence Based Management of Colorectal cancer

This review article examines the evidence-based management of colorectal cancers, focusing on topics characterized by ongoing debates and evolving evidence. To contribute to the scientific discourse, we intentionally exclude subjects with established guidelines, concentrating instead on areas where the current understanding is dynamic. Our analysis encompasses a thorough exploration of critical themes, including the evidence surrounding complete mesocolic excision and D3 lymphadenectomy in colon cancers. Additionally, we delve into the evolving landscape of perioperative chemotherapy in both colon and rectal cancers, considering its nuanced role in the context of contemporary treatment strategies. Advancements in surgical techniques are a pivotal aspect of our discussion, with an emphasis on the utilization of minimally invasive approaches such as laparoscopy and robotic surgery in both colon and rectal cancers, including advanced rectal cases. Moving beyond conventional radical procedures, we scrutinize the feasibility and implications of endoscopic resections for small tumors, explore the paradigm of organ preservation in locally advanced rectal cancers, and assess the utility of total neoadjuvant therapy in the current treatment landscape. Our final segment reviews pivotal trials that have significantly influenced the management of colorectal liver and peritoneal metastasis.

Complete mesocolic excision for right colon cancer: Is D3 lymphadenectomy necessary?

AIM

Although complete mesocolic excision (CME) for colon cancer is oncologically sound, to date, there has been no consensus on the extent of lymphadenectomy in radical right colectomy. This study essentially compared the perioperative and survival outcomes of CME with two templates of lymphadenectomy for right colon cancer.

METHOD

This was a propensity matched, retrospective analysis of a single centre, prospectively maintained database of all patients undergoing elective right colectomy for nonmetastatic, biopsy-proven adenocarcinoma from November 2013 to October 2018. CME + D3 was adopted selectively, documented prospectively, and compared with patients undergoing CME + central vascular ligation (CVL). The only technical difference between the groups was the excision of the surgical trunk of Gillot in the CME + D3 group. Postoperative, long-term outcomes and patterns of recurrence were compared between the groups.

RESULTS

Of the 244 eligible patients, 88 (36.1%) and 156 (63.9%) underwent CME + D3 and CME + CVL, respectively. Matched groups (72 [CME + D3] vs. 108 [CME + CVL]) showed no difference in histology, tumour grade, postoperative complications, mortality, and hospital stay. CME + D3 was preferentially performed laparoscopically (35.2% vs. 9%), was associated with lower blood loss (215 mL vs. 297 mL, p = 0.001), higher nodal yield (31 vs. 25 nodes, p = 0.003) and a higher incidence of chyle leak (4 vs. 0, p = 0.013). At a median follow-up of more than 57 months, there was no significant difference in local recurrence, disease-free or overall survival.

CONCLUSION

In this retrospective study, lymphadenectomy along the superior mesenteric vein, as a component of CME for right colon cancer, offered a higher nodal yield with no improvement in oncological outcome. Dissection of the SMV, over and above a D2 dissection, could therefore be restricted to specialized colorectal units until further studies establish the incremental oncological benefit of this extended lymphadenectomy or define a patient group in whom it is beneficial.

Complete mesocolic excision for right hemicolectomy: an updated systematic review and meta-analysis

PURPOSE

Complete mesocolic excision improves lymphadenectomy for right hemicolectomy and respects the embryological planes. However, its effect on cancer-free and overall survival is questioned. Therefore, we aimed to determine the potential benefits of the technique by performing a systematic review of the literature and meta-analysis of the available evidence.

METHODS

Web of Science, PubMed/Medline, and Embase were searched on February 22, 2023. Original studies on short- and long-term oncological outcomes of adult patients undergoing right hemicolectomy with complete mesocolic excision as a treatment for primary colon cancer were considered for inclusion. Outcomes were extracted and pooled using a model with random effects.

RESULTS

A total of 586 publications were identified through database searching, and 18 from citation searching. Exclusion of 552 articles left 24 articles for inclusion. Meta-analysis showed that complete mesocolic excision increased the lymph node harvest (5 studies, 1479 patients, MD 9.62, 95% CI 5.83-13.41, p > 0.0001, I2 84%), 5-year overall survival (5 studies, 2381 patients, OR 1.88, 95% CI 1.14-3.09, p = 0.01, I2 66%), 5-year disease-free survival (4 studies, 1376 patients, OR 2.21, 95% CI 1.51-3.23, p < 0.0001, I2 0%) and decreased the incidence of local recurrence (4 studies, 818 patients, OR 0.27, 95% CI 0.09-0.79, p = 0.02, I2 0%) when compared to standard right hemicolectomy. Perioperative morbidity was similar between the techniques (8 studies, 3899 patients, OR 1.04, 95% CI 0.89-1.22, p = 0.97, I2 0%).

CONCLUSION

Meta-analysis of observational and randomised studies showed that right hemicolectomy with complete mesocolic excision for primary right colon cancer improves oncologic results without increasing morbidity/mortality. These results need to be confirmed by high-quality evidence and randomised trials in selected patients to assess who may benefit from the procedure.

Patient perspectives on consequences of resection for colorectal cancer: A qualitative study

BACKGROUND

Colorectal cancer is diagnosed in approximately 500,000 patients each year in Europe, leading to a high number of patients having to cope with the consequences of resection for colorectal cancer. As treatment options tend to grow, more information on the effects of these treatments is needed to engage in shared decision-making. This study aims to explore the impact of resection for colorectal cancer on patients' daily life.

METHODS

Patients (≥18 years of age) who underwent an oncological colorectal resection between 2018 and 2021 were selected. Purposeful sampling was used to include patients who differed in age, comorbidity conditions, types of (neo)adjuvant therapy, postoperative complications and the presence/absence of a stoma. Semi-structured interviews were conducted, guided by a topic guide. Interviews were fully transcribed and subsequently thematically analysed using the framework approach. Analyses were carried out using the following predefined themes: (1) daily life and activities; (2) psychological functioning; (3) social functioning; (4) sexual functioning; and (5) healthcare experiences.

RESULTS

Sixteen patients with a follow-up period of between 0.6 and 4.4 years after surgery were included in this study. Participants reported several challenges experienced because of poor bowel function, a stoma, chemotherapy-induced neuropathy, fear of recurrence and sexual dysfunction. However, they reported these as not interfering much with daily life.

CONCLUSION

Colorectal cancer treatment leads to several challenges and treatment-related health deficits. This is often not recognized by generic patient-reported outcome measures, but the findings on treatment-related health deficits presented in this study contain valuable insights which might contribute to improving colorectal cancer care, shared decision making and value-based health care.

Complications after open and laparoscopic right-sided colectomy with central lymphadenectomy for colon cancer: randomized controlled trial

BACKGROUND

A central lymphadenectomy in right-sided colon cancer involves dissection along the superior mesenteric axis, but the extent is debated due to a lack of consensus and the fear of major complications. This randomized controlled trial compared the rate of postoperative morbidity in patients undergoing laparoscopic versus open right-sided colectomy with central lymphadenectomy.

METHODS

This open, prospective, randomized controlled trial compared patients operated on with open and laparoscopic right-sided colectomy (cStages I-III) with a central lymphadenectomy at two Norwegian institutions between October 2016 and December 2021. Dissections were conducted along the superior mesenteric vein in the laparoscopic group, and along the left anterior border of the superior mesenteric artery in the open group, both according to complete mesocolic excision principles. Surgery was standardized and performed by three experienced surgeons for each study group. The primary outcome of interest was to measure postoperative 30-day complications (Clavien-Dindo ≥ grade II).

RESULTS

Of 273 eligible patients, 135 were randomized and 128 analysed (63 operated on with open and 65 using laparoscopic procedures). Postoperative complications occurred in 42.8 per cent of the patients treated with open and 38.4 per cent of the patients treated using laparoscopic surgery, P = 0.372. The incidence of Clavien-Dindo grade IIIb complications was 7.9 per cent in the open versus 4.6 per cent in the laparoscopic group, P = 0.341. There were no grade IV or V complications, and no re-operations due to anastomotic leakages. There was no significant difference in the mean(s.e.m.) number of removed lymph nodes (open versus laparoscopic respectively: 31.9(1.8) versus 29.3(1.3); P = 0.235).

CONCLUSION

There was no significant difference in complications between the two groups. Standardized oncologic right-sided colectomy with central lymphadenectomy along the mesenterial root was performed safely, both open and laparoscopic, with incidence of major complications ranging between 4.6 and 7.9 per cent and no re-operations for anastomotic leakage. Radicality in terms of lymphadenectomy was comparable between the two groups.Registration number: NCT03776591 (http://www.clinicaltrials.gov).

Surgical and oncological outcomes of laparoscopic right hemicolectomy (D3 + CME) for colon cancer: A prospective single-center cohort study

BACKGROUND

Complete mesocolic excision (CME) or D3 lymphadenectomy led to survival benefits for locally advanced right colon cancer, but with vague definitions in anatomy and debated surgical hazard in clinic. Aiming to achieve a precise definition of it in anatomy, we proposed laparoscopic right hemicolectomy (D3 + CME) as a novel procedure for colon cancer. However, the surgical and oncological results of this procedure in clinic were uncertain.

METHODS

We performed a cohort study involving prospective data collected from a single-center in China. Data from all patients who underwent right hemicolectomy between January 2014 and December 2018 were included. We compared the surgical and oncological outcomes between D3 + CME and conventional CME.

RESULTS

After implementation of exclusion criteria, a total of 442 patients were included. D3 + CME group performed better in lymph nodes harvested (25.0 [17.0, 33.8] vs. 18.0 [14.0, 25.0], P < 0.001) and the proportion of intraoperative blood loss ≥ 50 mL (31.7% vs. 51.8%, P < 0.001); no significant difference was observed in the complication rates between two groups. Kaplan-Meier analysis demonstrated that a better cumulative 5-year disease-free survival (91.3% vs. 82.2%, P = 0.026) and a better cumulative 5-year overall survival (95.2% vs. 86.1%, P = 0.012) were obtained in the D3 + CME group. Multivariate COX regression revealed that D3 + CME was an independent protective factor for disease-free survival (P = 0.026).

CONCLUSION

D3 + CME could improve surgical and oncological outcomes simultaneously for right colon cancer compared to conventional CME. Large-scale randomized controlled trials were further required to confirm this conclusion, if possible.

Surgical efficacy and learning curves of laparoscopic complete mesocolic excision with intracorporeal anastomosis for right-sided colon cancer: A retrospective two-center cohort study

BACKGROUND

There is a potential benefit on long-term outcomes following complete mesocolic excision (CME) for right-sided colon cancer when compared to conventional colectomy. This study aims to analyze the learning curve and short-term outcomes of laparoscopic CME with intracorporeal anastomosis (ICA) for right-sided colon cancer in the hands of experienced colorectal surgeons.

METHODS

A two-center cohort study of consecutive patients undergoing right-sided colectomy from September 2021 to May 2022 at two tertiary colorectal centers in Denmark. Learning curves of surgical time were estimated using a cumulative sum analysis (CUSUM).

RESULTS

A total of 61 patients were included. According to the CUSUM analysis, 32 cases were needed to obtain a peak in operative time, resulting in a decrease in time consumption (group 1/learning phase: 217.2 min [SD 53.6] and group 2/plateau phase 191.6 min [SD 45.1], p = 0.05). There was a nonsignificant reduction in the rates of severe surgical complications (Clavien-Dindo > 3) (13% vs. 7%, p = 0.67) between the two groups, while the length of hospital stay remained constant (median 3.0 days, interquartile range, IQR [2.0; 4.0]).

CONCLUSION

The learning curve of laparoscopic CME with ICA for right-sided colon cancer demonstrated that 32 cases were needed to obtain a plateau phase expressed by operative time.

Survival Outcomes of Hepatectomy in Gastric Cancer Liver Metastasis: A Systematic Review and Meta-Analysis

Gastric cancer liver metastasis (GCLM) is a contraindication for surgical treatment in current guidelines. However, the results of recent studies are questioning this paradigm. We assessed survival outcomes and their predictors following hepatectomy for GCLM in a systematic review of studies published from 2000 to 2022 according to PRISMA guidelines. We identified 42,160 references in four databases. Of these, 55 articles providing data from 1990 patients fulfilled our criteria and were included. We performed a meta-analysis using random-effects models to assess overall survival (OS) and disease-free survival (DFS) at one, three, and five years post-surgery. We studied the impact of potential prognostic factors on survival outcomes via meta-regression. One, three, and five years after surgery, OS was 69.79%, 34.79%, and 24.68%, whereas DFS was 41.39%, 23.23%, and 20.18%, respectively. Metachronous presentation, well-to-moderate differentiation, small hepatic tumoral size, early nodal stage, R0 resection, unilobar compromisation, and solitary lesions were associated with higher overall survival. Metachronous presentation, smaller primary tumoral size, and solitary metastasis were linked to longer DFS. The results of our meta-analysis suggest that hepatectomy leads to favorable survival outcomes in patients with GCLM and provides data that might help select patients who will benefit most from surgical treatment.