Complete mesocolic excision in colorectal cancer: a systematic review

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.

Surgical quality assessment for the prospective study of oncologic outcomes after laparoscopic modified complete mesocolic excision for nonmetastatic right colon cancer (PIONEER study)

BACKGROUND

The modified complete mesocolic excision (mCME) procedure for right-sided colon cancer is a tailored approach based on the original complete mesocolic excision (CME) methodology. Limited studies evaluated the safety and feasibility of laparoscopic mCME using objective surgical quality assessments in patients with right colon cancer. The objectives of the PIONEER study were to evaluate oncologic outcomes after laparoscopic mCME and to identify optimal clinically relevant endpoints and values for standardizing laparoscopic right colon cancer surgery based on short-term outcomes of procedures performed by expert laparoscopic surgeons.

MATERIALS AND METHODS

This is an ongoing prospective, multi-institutional, single-arm study conducted at five tertiary colorectal cancer centers in South Korea. Study registrants included 250 patients scheduled for laparoscopic mCME with right-sided colon adenocarcinoma (from the appendix to the proximal half of the transverse colon). The primary endpoint was 3-year disease-free survival. Secondary outcomes included 3-year overall survival, incidence of morbidity in the first 4 weeks postoperatively, completeness of mCME, central radicality, and distribution of metastatic lymph nodes. Survival data will be available after the final follow-up date (June 2024).

RESULTS

The postoperative complication rate was 12.9%, with a major complication rate of 2.7%. In 87% of patients, central radicality was achieved with dissection at or beyond the level of complete exposure of the superior mesenteric vein. Mesocolic plane resection with an intact mesocolon was achieved in 75.9% of patients, as assessed through photographs. Metastatic lymph node distribution varied by tumor location and extent. Seven optimal clinically relevant endpoints and values were identified based on the analysis of complications in low-risk patients.

CONCLUSIONS

Laparoscopic mCME for right-sided colon cancer produced favorable short-term postoperative outcomes. The identified optimal clinically relevant endpoints and values can serve as a reference for evaluating surgical performance of this procedure.

Higher Numbers of Examined Lymph Nodes Are Associated with Increased Survival in Resected, Treatment-Naïve, Node-Positive Esophageal, Gastric, Pancreatic, and Colon Cancers

BACKGROUND OR PURPOSE

The role of extended lymphadenectomy as part of resection for lymph node (LN)-positive gastrointestinal (GI) malignancies remains controversial with no clear clinical guidance. The purpose of this retrospective study is to determine whether the number of LNs examined as part of GI malignancy resections affects overall survival (OS) among patients with node-positive esophageal, gastric, pancreatic, and colon cancers.

METHODS

Participants with LN-positive GI cancers who were diagnosed between 2004 and 2015 and underwent oncologic resections were selected from National Cancer Database (NCDB). The primary predictor was the number of examined LNs categorized in tertiles. The effect on OS was measured by hazard ratio (HR) derived from multivariate Cox regression analyses.

RESULTS

From 2004 to 2015, 1877, 10,086, 18,193, and 102,500 patients with LN-positive esophageal, gastric, pancreatic, and colon adenocarcinomas who did not receive neoadjuvant treatment and underwent oncologic tumor resection were registered in the NCDB. Using multivariate Cox proportional hazard modeling, greater LNs examined in surgically resected LN-positive GI cancers were found to be associated with increased OS for all histologies. This association was the strongest (as compared to the lowest tertile) for gastric cancer (middle tertile: HR = 0.91, 95% CI, 0.86-0.96, p = 0.001; highest tertile: HR = 0.73, 95% CI, 0.69-0.78, p < 0.001), followed by colon (highest tertile: HR = 0.86, 95% CI, 0.84-0.88, p < 0.001), esophageal (highest tertile: HR = 0.83, 95% CI, 0.72-0.95, p = 0.01), and pancreatic (highest tertile: HR = 0.93, 95% CI, 0.89-0.98, p = 0.002) cancers.

DISCUSSION AND CONCLUSION

In patients with surgically resected node-positive GI malignancies who did not receive neoadjuvant systemic therapy, a higher number of examined LNs is associated with increased OS. This association is the strongest for gastric cancer, followed by colon, esophageal, and pancreatic cancers respectively.

Colorectal cancer

Although surgery is the established standard and mainstay for treatment of colorectal cancer, advances in technology and clinical trials over the past 50 years have dramatically expanded and improved the detection, staging, treatment, and understanding of this disease. This review highlights contributions by surgeons, oncologists, gastroenterologists, engineers, and scientists to increase postsurgical recurrence-free survival, reduce the time and toxicity of treatment, and improve the quality of life for patients over the past half-century.

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

BACKGROUND

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

METHOD

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

RESULTS

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

CONCLUSION

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

Qualitative umbrella review of systematic reviews on complete mesocolic excision for colon cancer

BACKGROUND

Complete mesocolic excision (CME) of colon cancer with extended lymphadenectomy was suggested to improve radical resection of colon cancer. This comprehensive review aimed to assess the current literature for the outcomes of CME of colon cancer through an appraisal of the findings of published systematic reviews and meta-analyses.

METHODS

A systematic literature review searching for the studies that assessed the outcome of CME of colon cancer was conducted. Electronic databases were queried from 2009 through November 2020. The main objectives of this review were to illustrate the technical aspects and outcome of CME and to summarize the findings of the published systematic reviews.

RESULTS

Thirteen systematic reviews were retrieved. All reviews found CME to provide longer bowel, larger area of mesentery resected, and more lymph nodes (LNs) retrieved than standard colectomy. All systematic reviews except two found similar complication rates between CME and standard colectomy. Four systematic reviews documented the survival benefit of CME in regards to improved overall and disease-free survival. Using the laparoscopic approach for CME did not compromise the oncologic outcomes of the procedures, yet was associated with less intraoperative blood loss, faster recovery, and potential survival benefits.

CONCLUSIONS

CME is associated with better specimen quality, more LNs clearance, and potential survival benefits compared to standard colectomy. However, the lack of robust data from well-designed multicenter randomized trials may prevent drawing firm conclusions on the oncologic benefits of CME. Further high-quality studies are needed before recommending CME as the standard of care for colon cancer.

Pattern of recurrence and survival after D2 right colectomy for cancer: is there place for a routine more extended lymphadenectomy?

BACKGROUND

Conventional Right Colectomy with D2 lymphadenectomy (RC-D2) currently represent the most common surgical treatment of right-sided colon cancer (RCC). However, whether it should be still considered a standard of care, or replaced by a routine more extended D3 lymphadenectomy remains unclear. In the present study, we aim to critically review the patterns of relapse and the survival outcomes obtained from our 11-year experience of RC-D2.

METHODS

Clinical data of 489 patients who underwent RC-D2 for RCC at two centres, from January 2009 to January 2020, were retrospectively reviewed. Patients with synchronous distant metastases and/or widespread nodal involvement at diagnosis were excluded. Post-operative clinical-pathological characteristics and survival outcomes were evaluated including the pattern of disease relapse.

RESULTS

We enrolled a total of 400 patients with information follow-up. Postoperative morbidity was 14%. The median follow-up was 62 months. Cancer recurrence was observed in 55 patients (13.8%). Among them, 40 patients (72.7%) developed systemic metastases, and lymph-node involvement was found in 7 cases (12.8%). None developed isolated central lymph-node metastasis (CLM), in the D3 site. The estimated 3- and 5-year relapse-free survival were 86.1% and 84.4%, respectively. The estimated 3- and 5-year cancer-specific OS were 94.5% and 92.2%, respectively.

CONCLUSIONS

The absence of isolated CLM, as well as the cancer-specific OS reported in our series, support the routine use of RC-D2 for RCC. However, D3 lymphadenectomy may be recommended in selected patients, such as those with pre-operatively known CLM, or with lymph-node metastases close to the origin of the ileocolic vessels.

Multidimensional evaluation of the learning curve for laparoscopic complete mesocolic excision for right colon cancer: a risk-adjusted cumulative summation analysis

AIM

Despite the suggested potential benefit of complete mesocolic excision (CME) for right-sided colon cancer (RCC) for patient survival, concerns about its safety and feasibility have contributed to delayed acceptance of the procedure, especially when performed by a minimally invasive approach. Thus, the aim of this work was to evaluate the actual learning curve (LC) of laparoscopic CME for experienced colorectal surgeons.

METHOD

Prospectively collected data for consecutive patients undergoing laparoscopic CME for RCC between October 2015 and January 2021 at our institution, operated on by experienced surgeons, were analysed. A multidimensional assessment of the LC was performed through cumulative sum (CUSUM) and risk-adjusted (RA) CUSUM analysis.

RESULTS

Two hundred and two patients operated by on by three surgeons were considered. The CUSUM graphs based on operating time showed one peak of the curve between 17 and 27 cases. The CUSUM graphs based on surgical failure showed one peak of the curve between 20 and 24 cases The RA-CUSUM curve also showed one preeminent peak at 24-33 cases. Based on the CUSUM and RA-CUSUM analyses all the surgeons reached proficiency in 24-33 cases.

CONCLUSIONS

Our study showed that an experienced minimally invasive colorectal surgeon acquires proficiency in laparoscopic CME for RCC after performing 24-33 cases.

Extended Versus Standard Complete Mesocolon Excision in Sigmoid Colon Cancer: A Multicenter Randomized Controlled Trial

OBJECTIVE

The aim of this study was to evaluate whether extended complete mesocolic excision (e-CME) for sigmoid colon cancer improves oncological outcomes without compromising morbidity or functional results.

BACKGROUND

In surgery for cancer of the sigmoid colon and upper rectum, s-CME removes the lymphofatty tissue surrounding the inferior mesenteric artery (IMA), but not the lymphofatty tissue surrounding the portion of the inferior mesenteric vein that does not run parallel to the IMA. Evidence about the safety and efficacy of extending CME to include this tissue is lacking.

METHODS

This single-blind study randomized sigmoid cancer patients at 4 centers to undergo e-CME or s-CME. The primary outcome was the total number of lymph nodes harvested. Secondary outcomes included disease-free and overall survival at 2 years, morbidity, and bowel and genitourinary function. Clinicaltrials.gov: NCT03107650.

RESULTS

We analyzed 93 patients (46 e-CME and 47 s-CME). Perioperative outcomes were similar between groups. No differences between groups were found in the total number of lymph nodes harvested [21 (interquartile range, IQR, 14-29) in e-CME vs 20 (IQR, 15-27) in s-CME, P = 0.873], morbidity (P = 0.829), disease-free survival (P = 0.926), or overall survival (P = 0.564). The extended specimen yielded a median of 1 lymph node (range, 0-6), none of which were positive.Bowel function recovery was similar between arms at all timepoints. Males undergoing e-CME had worse recovery of urinary function (P = 0.026).

CONCLUSION

Extending lymphadenectomy to include the IMV territory did not increase the number of lymph nodes or improve local recurrence or survival rates.

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

AIM

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Robotic complete mesocolic excision versus conventional robotic right colectomy for right-sided colon cancer: a comparative study of perioperative outcomes

AIM

This study aims to compare the short-term outcomes of robotic complete mesocolic excision (RCME) versus conventional robotic right colectomy (RRC) for right-sided colon cancer.

METHODS

Consecutive patients who underwent robotic surgery for right-sided colon cancer in a public quaternary and a private tertiary healthcare centre between November 2018 and June 2020 were included. Clinical, perioperative and histopathological variables were collected and analysed.

RESULTS

Fifty-one patients were included; 25 (49%) of them had an RCME. The groups were evenly distributed in terms of demographic characteristics and tumour location. Operative time was similar between both groups, and no patients required conversion to open surgery. There were no differences in overall complications (16% in RCME vs. 26.9% in RRC; p = 0.499) or their profile between groups. There were no anastomotic leaks recorded, and the reoperation rates were similar (0% for RCME versus 3.8% for RRC; p = 1). In addition, the median length of hospital stay was similar in between the RCME and the RRC groups (4 [4-6] days versus 5 [3-8.5] days, respectively; p = 0.891). Whilst there were no differences in the TNM staging, the mean number of lymph nodes harvested with RCME was 37.7 (±12.9) compared to 21.8 (±7.5) with RCC (p < 0.001).

CONCLUSION

In our series, RCME was associated with a higher lymph node harvest and a similar morbidity profile compared to RCC. Further studies are required to validate these results and provide long-term oncologic outcomes.

Elderly Patients Have Better Quality of Life but Worse Survival Following Pelvic Exenteration: A 25-Year Single-Center Experience

OBJECTIVE

To describe quality of life (QOL) and survival outcomes following pelvic exenteration (PE) in old and young patients.

BACKGROUND

PE is a management option for complete resection in locally advanced pelvic cancers. Few studies have examined the impact of age on the outcome in elderly patients following PE.

PATIENTS AND METHODS

Prospective cohort of consecutive patients undergoing partial and complete PE between 1994 and 2019. Patients were divided into a younger (< 65 years) or older cohort (≥ 65 years) based on their age. QoL was assessed using the SF-36 and FACT-C questionnaires and survival estimated using the Kaplan-Meier method.

RESULTS

For 710 patients who underwent PE during the study period, FACT-C total score was significantly better in the elderly during the whole follow-up period of 5 years. Mental component score (SF-36) was significantly better at baseline (p = 0.008) and at 24 months postoperatively (p = 0.042), in the elderly group. Median overall survival was 75 months in the younger cohort and 53 months in the older cohort (p = 0.004). In subgroup analysis, older patients with recurrent or primary rectal cancer had a median survival of 37 and 70 months, respectively. Postoperative cardiovascular complications were greater in the elderly cohort (p < 0.001).

CONCLUSIONS

Elderly patients had better overall QoL but lower survival that is probably related to cardiovascular complications rather than to cancer as both groups had similar R0 resection rate. Hence, the elderly population should be considered equally for PE.

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

BACKGROUND

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

METHODS

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

FINDINGS

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

INTERPRETATION

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

FUNDING

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

Surgical oncology in the age of multimodality therapy for cancer of the upper and lower gastrointestinal tract

INTRODUCTION

To date, all efforts to fight gastrointestinal cancer, regardless of its origin and entity, have resulted in complex therapeutic regimens involving a combination of systemic therapy, radiation therapy and surgery. It is generally accepted across all disciplines that not one, but the combination and the proper timing of all modalities result in the best oncologic outcome.

AREAS COVERED

Here, we provide insight into the current and future value of multimodal therapeutic approaches for upper and lower gastrointestinal cancer. Various aspects of treatment as well as open questions regarding indication and timing of multimodal strategies are addressed in this review.

EXPERT OPINION

In order to further improve the survival and quality of life of patients with gastrointestinal tumors in the future, scientifically proven multimodal therapy concepts are needed first and foremost. In addition, markers are pivotal to assign individual patients to a specific concept and to monitor the success of therapy. The main question is in which situation a neoadjuvant, perioperative or adjuvant radio-, chemo- or immunotherapy is superior. In fact, almost every curatively intended concept still contains surgical resection. Thus, improvement in surgical technique is also critical for multimodality concepts.

Laparoscopic Versus Open Complete Mesocolon Excision in Right Colon Cancer: A Systematic Review and Meta-Analysis

BACKGROUND

Laparoscopic complete mesocolon excision (LCME) for right colonic cancer improves oncological outcomes. This systematic review and meta-analysis aimed to compare intraoperative, postoperative, and oncological outcomes after LCME and open total mesocolon excision (OCME) for right-sided colonic cancers.

METHODS

Literature searches of electronic databases and manual searches up to January 31, 2019, were performed. Random-effects meta-analysis model was used. Review Manager Version 5.3 was used for pooled estimates.

RESULTS

After screening 1334 articles, 10 articles with a total of 2778 patients were eligible for inclusion. Compared to OCME, LCME improves results in terms of overall morbidity (OR = 1.48, 95% CI 1.21 to 1.80, p = 0.0001), blood loss (MD = 56.56, 95% CI 19.05 to 94.06, p = 0.003), hospital stay (MD = 2.18 day, 95% CI 0.54 to 3.83, p = 0.009), and local (OR = 2.12, 95% CI 1.09 to 4.12, p = 0.03) and distant recurrence (OR = 1.63, 95% CI 1.23-2.16, p = 0.0008). There was no significant difference regarding mortality, anastomosis leakage, number of harvested lymph nodes, and 3-year disease-free survival. Open approach was significantly better than laparoscopy in terms of operative time (MD = - 34.76 min, 95% CI - 46.01 to - 23.50, p < 0.00001) and chyle leakage (OR = 0.41, 95% CI 0.18 to 0.96, p = 0.04).

CONCLUSIONS

This meta-analysis suggests that LCME in right colon cancer surgery is superior to OCME in terms of overall morbidity, blood loss, hospital stay, and local and distant recurrence with a moderate grade of recommendation due to the retrospective nature of the included studies.

Prospective study of oncologic outcomes after laparoscopic modified complete mesocolic excision for non-metastatic right colon cancer (PIONEER study): study protocol of a multicentre single-arm trial

Background

The introduction of complete mesocolic excision (CME) with central vascular ligation (CVL) for right-sided colon cancer has improved the oncologic outcomes. Recently, we have introduced a modified CME (mCME) procedure that keeps the same principles as the originally described CME but with a more tailored approach. Some retrospective studies have reported the favourable oncologic outcomes of laparoscopic mCME for right-sided colon cancer; however, no prospective multicentre study has yet been conducted.

Methods

This study is a multi-institutional, prospective, single-arm study evaluating the oncologic outcomes of laparoscopic mCME for adenocarcinoma arising from the right side of the colon. A total of 250 patients will be recruited from five tertiary referral centres in South Korea. The primary outcome of this study is 3-year disease-free survival. Secondary outcome measures include 3-year overall survival, incidence of surgical complications, completeness of mCME, and distribution of metastatic lymph nodes. The quality of laparoscopic mCME will be assessed on the basis of photographs of the surgical specimen and the operation field after the completion of lymph node dissection.

Discussion

This is a prospective multicentre study to evaluate the oncologic outcomes of laparoscopic mCME for right-sided colon cancer. To the best of our knowledge, this will be the first study to prospectively and objectively assess the quality of laparoscopic mCME. The results will provide more evidence about oncologic outcomes with respect to the quality of laparoscopic mCME in right-sided colon cancer.

Trial registration

ClinicalTrials.gov ID: NCT03992599 (June 20, 2019). The posted information will be updated as needed to reflect protocol amendments and study progress.

Minimally invasive complete mesocolic excision and central vascular ligation (CME/CVL) for right colon cancer

Total mesorectal excision (TME) is the standard of care in rectal cancer surgery. Complete mesocolic excision and central vascular ligation (CME and CVL) are surgical concepts that are extrapolated from the principles of TME. Increasingly adopted by surgical units worldwide, laparoscopic CME/CVL for right sided colon cancer is a challenging procedure that requires meticulous dissection by the surgeon and detailed knowledge of the colonic vascular anatomy. This review article addresses the main issues pertaining to this surgical technique and also discusses steps on how to perform this operation safely.

Recurrence and Long-Term Survival Following Segmental Colectomy for Right-Sided Colon Cancer in 813 Patients: a Single-Institution Study

BACKGROUND

Controversy exists regarding optimal surgical approach to right-sided colon cancer due to increasing complete mesocolic excision outcome data; yet, scarce long-term surgical and oncologic outcome data from high-volume centers following right segmental resections without complete mesocolic excision make comparisons difficult to interpret. We report long-term outcomes following standard mesocolic excision for right-sided colon adenocarcinoma.

METHODS

A retrospective review of a prospective database was conducted of all consecutive adult patients undergoing surgery for a right-sided colon adenocarcinoma between 2000 and 2007. Demographics, oncologic, operative, and pathologic details are reported. Primary endpoints consisted of overall survival and recurrence. Patients with stage IV and recurrent disease were excluded.

RESULTS

Eight hundred thirteen patients were identified. Majority of tumors were stage II (n = 318, 39%). Adjuvant chemotherapy was administered to 228 patients (28%). Recurrence was observed in 97 patients (12%), at median 1.3 years. Recurrence was most commonly distant (n = 73, 9%). At median follow-up 7.3 years, 5- and 10-year overall survival was 72.4%, and 48.6%, respectively. Five- and 10-year disease-free survival was 67% and 45.8%, respectively. Multivariable analysis demonstrated that TNM stage was a significant predictor of recurrence. For disease-free survival, T stage, and N stage were significant on multivariate analysis. Multivariable predictors of overall survival included age, number of lymph nodes removed, N stage, and adjuvant chemotherapy use.

CONCLUSIONS

Excellent long-term outcomes from a large cohort of patients with non-metastatic, right colon adenocarcinoma treated by segmental colectomy without complete mesocolic excision are reported. The majority of recurrences were distant.

Long-term outcomes after complete mesocolic excision for colon cancer at a tertiary care center in Saudi Arabia

BACKGROUND

Data on long-term survival and recurrence of cancer after complete mesocolic excision (CME) for colon cancer has not been reported from our center and related to international data.

OBJECTIVE

Describe overall and disease-free survival, survival by surgery site and stage, and recurrence rates after curative surgery.

DESIGN

Retrospective chart review.

SETTINGS

Academic tertiary care center.

PATIENTS AND METHODS

The study included all patients who underwent either laparoscopic or open surgery for colon cancer with curative intent between 2001 and 2011. The colorectal database was reviewed for the following: demographic data, comorbidities, radiologic investigations, clinical stage, type of operation, complications, pathologic assessment, adjuvant treatment, recurrence and survival. Survival and recurrence rates were calculated, and survival curves were generated.

MAIN OUTCOME MEASURES

5-year overall survival, secondary endpoints were 5-year disease-free survival, survival by surgery site and stage, and recurrence rates.

SAMPLE SIZE

220.

RESULTS

The mean (SD) age at diagnosis was 57 (13) years (CI 95%: 55-59 years). There were 112 males. Mean (SD) body mass index was 27.6 (5.7) kg/m² (CI 95%: 27-28). Pathological assessment revealed R0 (microscopically margin-negative) resection in 207 (94%). The overall 5-year survival and disease-free survival was 77.9% and 70%, respectively. The 5-year disease-free survival was 69% for the sigmoid/left colon and 69% for the right colon (difference statistically nonsignificant). Stages at the time of resection were stage 0 for 2 (0.01%) patients, stage I for 18 (8%), stage II for 92 (42%), stage III for 100 (46%), and stage IV for 6 (3%). The 5-year overall survival by stages I, II, III and IV was 94%, 80%, 75% and 50%, respectively (difference statistically non-significant). The overall 5-year recurrence rate was 23.4%.

CONCLUSION

The outcomes of surgical treatment for colon cancer at our institution are equivalent to international sites. No difference was noted between left and right colon in terms of survival after CME.

LIMITATIONS

Single center, retrospective, small sample size.

CONFLICT OF INTEREST

None.

Robotic complete mesocolic excision using indocyanine fluorescence imaging in colorectal cancer: A case study and technical approach

•

Complete mesocolic excision confers a possible survival advantage in right sided colorectal cancer.

•

Indocynanine Green (ICG) Fluorescence Imaging may allow for more targeted lymph node clearances.

•

Robotic surgery allows for these nodes to be removed with an MIS approach.

Introduction

Colorectal cancer is the second most common malignancy in developed countries and accurate staging is vital for determining the most appropriate management plan, in particular, whether adjuvant chemotherapy is recommended in addition to surgical resection. There is currently no consensus regarding standard practice for lymph node resection in colorectal cancer although there is increasing evidence to support the use of sentinel lymph node mapping to target lymph node sampling and facilitate ultra-staging of nodes.

Presentation of case

We present the case of a 49 year old female who underwent a robotic right hemicolectomy and complete mesocolic excision for caecal adenocarcinoma using indocyanine fluorescence imaging (ICG FI) to guide nodal dissection.

Discussion

ICG FI may be useful for sentinel lymph node mapping in colorectal cancer. This technique can assist to identify the first draining lymph nodes and permit ultra-staging of lymph nodes.

Conclusion

While there is still limited evidence to support ICG FI, the current body of literature suggests that it is likely to be a feasible and sensitive technique for guiding sentinel lymph node sampling in colorectal cancer.

How does lymph node yield affect survival outcomes of stage I and II colon cancer?

Background

According to the American Joint Committee on Cancer staging for cancer of the colon, a minimum of 12 lymph nodes (LN) has to be sampled for accurate staging. This has bearing on the long-term prognosis and the need for adjuvant chemotherapy. The aim of this study was to revisit the association of lymph node yield and the long-term survival in patients with stages I and II, i.e. node-negative, colon cancer.

Method

Consecutive patients who underwent elective or emergency curative resections for cancer of colon between the years 2003 and 2012 were retrospectively reviewed. Only patients with stage I or II diseases (AJCC 8th edition) were included. They were analysed in three groups, LN<12, LN12-19 and LN≥20. Their clinic-pathological characteristics were compared. The disease-free (DFS) and overall survival (OS) were estimated with the Kaplan-Meier method and compared with the log-rank test.

Results

There was a total of 659 patients included in the analysis. Twelve or more LN were found in 65.6% of the specimens. The mean follow-up was 83.9 months. LN≥20 had significantly better DFS (p = 0.015) and OS (p = 0.036), whereas LN<12 had similar DFS and OS when compared to LN12-19. The advantage in DFS and OS were mainly seen in those with stage II diseases. A lymph node yield of greater than 20 was one of the predictors of favourable DFS, hazard ratio 0.358; 95% CI 0.170–.756, p = 0.007.

Conclusion

The lymph node yield had a significant association with survival outcomes. A lymph node yield of 20 or more was associated with better survival outcomes. On the other hand, lymph node yield less than 12 was not shown to have inferior survival outcomes when compared to those between 12 and 19.

Introduction of complete mesocolic excision with central vascular ligation as standardized surgical treatment for colon cancer in Greece. Results of a pilot study and bi-institutional cooperation

INTRODUCTION

Complete mesocolic excision (CME) is generally accepted as state of the art in colon cancer surgery. However, the long-term impact of CME has not been systematically examined. Therefore cohort studies might be a possible way to clarify any differences between conventional resections and CME. Following bilateral cooperation between the Department of Surgery/University Hospital of Erlangen and the 1st Surgical Department of the General Hospital of Nikaia/Piraeus, including teaching activities for introduction of CME, a cohort study was performed, considering surgical quality criteria and clinical outcome.

MATERIAL AND METHODS

All patients with colon carcinomas (CME group, n = 31) referred to the 1st Surgical Department of General Hospital, Nikaia/Piraeus, Greece for surgery from January 2012 to December 2013 were prospectively analyzed and compared with patients who underwent conventional surgery for colon cancer between January 2008 and December 2011 (non-CME group, n = 35). Patients' follow-up was at least 48 months.

RESULTS

There were significantly better results in terms of lymph node yield (CME group: 29.6 vs. non-CME group: 17.85; p < 0.001) and lymph node ratio (LNR) (CME group: 0.12 vs. non-CME group: 0.24; p < 0.001) and recurrence-free survival in favor of the CME group (CME group: n = 0 vs. non-CME group: n = 5) without any increase in surgical morbidity (CME group: n = 6 vs. non-CME group: n = 11; p = 0.10).

CONCLUSIONS

Complete mesocolic excision appears to offer a superior oncological result without any increase of postoperative morbidity and mortality. Furthermore, CME represents a surgical technique which can be established in a surgical department after previous teaching without increasing the postoperative complication rate.

Impact of tumor sidedness on survival and recurrence patterns in colon cancer patients

Purpose

Previous studies have reported conflicting results regarding the prognostic value of tumor sidedness in colon cancer. We investigated the oncologic impact of tumor location and examined whether recurrence patterns were related to tumor sidedness in colon cancer patients.

Methods

We identified stage I-III colon adenocarcinoma patients from a prospective colorectal cancer registry at Severance Hospital, Seoul, Korea, who underwent complete mesocolic excision between 2005 and 2012. Adjusted hazard ratios (HRs) and 95% confidence intervals (CI) for predictors of cancer-specific survival (CSS), recurrence-free survival (RFS), and cumulative recurrence at specific anatomic sites were examined using Cox proportional hazard regression analysis.

Results

Overall, 1,912 patients, 1,077 (56.3%) with left-sided colon cancer (LCC), and 835 (43.7%) with right-sided colon cancer (RCC), at a median follow-up of 59 months, were eligible and included in the study. In univariate analysis, similar 5-year CSS and RFS were observed for LCC and RCC in the total patient population, and when stratified by stage for stage I and II patients. For stage III patients, an adjusted Cox regression analysis indicated that RCC patients had a higher risk of cancer-specific mortality (HR, 1.75; 95% CI, 1.07-2.86; P = 0.024) and recurrence (HR, 1.78; 95% CI, 1.22-2.60; P = 0.003). Furthermore, RCC was an independent predictor of peritoneal recurrence (HR, 1.86; 95% CI, 1.05-3.29; P = 0.031) in stage III patients.

Conclusion

RCC correlated with worse CSS and RFS than LCC. In stage III patients, RCC correlated with increased risk of peritoneal recurrence. The reasons for these differences remain to be investigated.

[Quality indicators for colon cancer surgery : Evidence-based development of a set of indicators for the outcome quality]

BACKGROUND

Quality assessment in surgery is gaining in importance. Although sporadic recommendations for quality indicators (QI) in oncological colon surgery can be found in the literature, these are usually not systematically derived from a solid evidence base. Moreover, reference ranges for QI are unknown.

OBJECTIVE

The aim of this initiative was the development of evidence-based QI for oncological colon resections by an expert panel invited by the German Society of General and Visceral Surgery (DGAV). Reference ranges from the literature and reference values from the Study, Documentation, and Quality Center (StuDoQ)|Colon Cancer Register were compared in order to deduce recommendations which are tailored to the German healthcare system.

RESULTS

Based on the most recent scientific evidence and agreed by expert consensus, five QI for oncological colon surgery were defined and evaluated according to the QUALIFY tool. Mortality, MTL30 (mortality, transfer to another acute care hospital, or length of stay ≥30 days), anastomotic leakage requiring reintervention, surgical site infections necessitating reopening of the wound and ≥12 lymph nodes in the specimen qualified as QI owing to their relevance, scientific nature, and practicability. Based on the results of the systematic literature search and the statistical analysis of the StuDoQ|Colon Cancer Register, preliminary reference values are proposed for each QI.

CONCLUSION

The presented set of QI seems appropriate for quality assessment of oncological colon surgery in the context of the German healthcare system. The validity of the QI and the reference values must be reviewed within the framework of their implementation. The StuDoQ|Colon Cancer Register provides a suitable infrastructure for collecting clinical data for quality assessment and risk adjustment.

Four-directional approach to the meso-transverse attachment combined with preoperative radiological vascular simulation facilitates short-term surgical outcomes in laparoscopic transverse colon cancer surgery

INTRODUCTION

Transverse colon resection is one of the most difficult laparoscopic procedures because of anatomic hazards such as variations in the mesenteric vascular anatomy and the complex structure of organs and surrounding membranes.

METHODS

We evaluated the short-term surgical outcomes of laparoscopic transverse colon resection using a creative approach. This approach included preoperative surgical simulation using virtual surgical anatomy by CT, a four-directional approach to the mesentery, and 3-D imaging during laparoscopic surgery.

RESULTS

A total of 45 consecutive patients who underwent laparoscopic resection for transverse colon cancer from June 2013 to December 2017 were enrolled in this study. All procedures were completed safely, with minor postoperative complications, including two patients with anastomotic stenosis, two with intra-abdominal phlegmon, one with delayed gastric emptying, and one with pneumonia, all treated non-operatively. There were no conversions to open resection. Operation time was 203 min (range, 125-322 min), and the estimated blood loss during surgery was 5 mL (range, 0-370 mL). The mean postoperative hospital stay was 10 days (range, 7-21 days), and no patients required readmission.

CONCLUSION

Short-term surgical outcomes after laparoscopic transverse colon resection demonstrated that this creative approach was safe and feasible. The four-directional approach to the meso-transverse attachment combined with preoperative radiological simulation can facilitate laparoscopic transverse colon surgery.

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.

Robotic left colectomy with complete mesocolectomy for splenic flexure and descending colon cancer, compared with a laparoscopic procedure

BACKGROUND

Its relatively low incidence and its surgical complexity mean that a standardized technique for left colectomy has not yet been established for splenic flexure and descending colon cancer (SF-DCC).

METHODS

Seventy-three patients (robot-assisted left colectomy with complete mesocolectomy [R-LCCM], n = 20; laparoscopic left colectomy with complete mesocolectomy [L-LCCM], n = 53) with SF-DCC were enrolled at the Asan Medical Center (Seoul, Korea).

RESULTS

R-LCCM conveniently enables dexterous dissection for the multi-directional approaches during left mesocolic mobilization. A conversion to open surgery was required in two patients of the L-LCCM group, but not in the R-LCCM group. A positive circumferential resection margin was exclusively identified in two patients in the L-LCCM group. Mean lymph node harvest was 21 with no difference between the two groups.

CONCLUSIONS

Although R-LCCM provided few remarkable advantages over L-LCCM, it could be considered as an efficient approach in patients with SF-DCC.

Risk Factors for Complications following Introduction of Radical Surgery for Colon Cancer: A Consecutive Patient Series

BACKGROUND

Rectal cancer surgery is standardized, resulting in improved survival. Colon cancer has fallen behind and therefore more radical surgical techniques have been introduced. One technique is complete mesocolic excision. The aim of this article was to study the complications after the introduction of standardized complete mesocolic excision in a single center.

METHODS

Complete mesocolic excision was introduced in 2007, and data were collected from 286 patients prior to surgery (2007-2010). The surgeon decided on open or laparoscopic surgery. Follow-up information was recorded until 31 December 2015. Complications were classified according to a modified Clavien-Dindo classification.

RESULTS

Complications occurred in 47%, severe complications (grade III and IV) in 15%. In-hospital mortality was 3.5%. A total of 142 patients (49.7%) were operated by open surgery. Logistic regression revealed anemia (p = 0.001), open surgery (p < 0.001), and long operating time (p < 0.001) as significant factors for complications in general. Multinomial logistic regression revealed that severe complications occurred more often in males (odds ratio: 2.56; 95% confidence interval: 0.98-6.68), patients with anemia (odds ratio: 3.49; 95% confidence interval: 1.27-9.60), elevated body mass index (odds ratio: 1.14; 95% confidence interval: 1.02-1.28), and in open surgery (odds ratio: 9.95; 95% confidence interval: 2.58-38.35). Age was not associated with severe complications. Survival was not significantly influenced by complications. Overall survival (5 years) was 90% among patients with complications and 92% among those without complications.

CONCLUSION

Severe complications following the introduction of complete mesocolic excision are patient dependent and related to open surgery. Patients selected for laparoscopy had less number of complications; therefore, introducing complete mesocolic excision by laparoscopy is justified. Identification of these factors can improve selection of appropriate surgical approach and postoperative patient safety.

Oncological outcomes of complete versus conventional mesocolic excision in laparoscopic right hemicolectomy

BACKGROUND

Complete mesocolic excision (CME) has been proposed for colon cancer to improve oncological outcomes. The risks and benefits of laparoscopic CME have not been examined fully. We compared short- and long-term outcomes of CME with a conventional mesocolic excision (non-CME) in laparoscopic right hemicolectomy (RHC) for right-sided colon cancer.

METHODS

In total, 115 patients who underwent laparoscopic RHC with stage I-III right-sided colon cancer at Busan Paik Hospital from August 2007 to October 2011 were enrolled in this case-control study. Three trained colorectal surgeons reviewed videos of the surgeries; patients were divided into two groups: those who underwent a CME (CME group, n = 34) and those who underwent a conventional mesocolic excision (non-CME group, n = 81).

RESULTS

There was no significant difference between the CME and non-CME groups in operative time, post-operative complications, or hospital stay. However, the CME group had more lymph nodes harvested (P < 0.001) and lower blood loss (P = 0.016) versus the non-CME group. There was no difference in 5-year disease-free survival rate between the groups, but 5-year overall survival rate was 100% in the CME group and 89.49% in the non-CME group (P < 0.05).

CONCLUSIONS

Laparoscopic RHC with CME is safe and associated with better 5-year overall survival rate than non-CME for patients with stage I-III right-sided colon cancer. Implementation of CME surgery might improve oncological outcomes for patients with right-sided colon cancer.

Complete mesocolic excision in right-sided colon cancer does not increase severe short-term postoperative adverse events

AIM

The aim was to assess whether complete mesocolic excision (CME) in patients with right-sided colon cancer is related to short-term mortality or postoperative adverse events requiring reoperation. The complete mobilization of an integral mesocolon and central ligation of blood vessels are essential steps in CME surgery. The resultant specimen, with an intact mesocolic fascia and a high number of harvested lymph nodes, is believed to be oncologically favourable. However, it has been suggested that CME surgery may increase the risk of intra-operative severe adverse events, due to exposure of vital retroperitoneal organs and large blood vessels.

METHOD

In a population-based, nested case-control study, all residents in the Stockholm County operated for right-sided colon cancer from 2004 until 2012 were identified from the Swedish Colorectal Cancer Registry. Patients who died within 90 days after surgery or were reoperated within 30 days after surgery, or during the index hospital stay, were defined as cases. Two controls per case were randomly sampled and individually matched for age, sex, TNM stage and emergency vs elective surgery. Exposure status (CME surgery) was assessed from original surgical reports.

RESULTS

The estimated proportion of CME surgery was 14.8% (35 of 236) for cases and 19.5% (92 of 473) for controls. The unadjusted OR for short-term mortality or reoperation after CME surgery was 0.72 (95% CI: 0.47-1.10; P = 0.15). The ORs were lower in the late part of the study (0.51; 95% CI: 0.26-1.01) and in high volume hospitals (0.61, 95% CI: 0.35-1.06).

CONCLUSIONS

The present study does not indicate that CME surgery is associated with an increased risk of severe adverse events such as 90-day mortality or reoperation.

Session 1: Colon cancer - 10 years behind the rectum

The improvements in surgical technique brought about by the widespread adoption of total mesorectal excision plane dissection in rectal cancer has substantially improved survival and recurrence rates from this disease. For the first time in 50 years, the outcomes in rectal cancer have overtaken those of colon cancer. Professor Madoff's overview lecture and the experts' round table discussion address whether applying the surgical principles already achieved in rectal cancer can meet with similar success in colon cancer, how this can be achieved and the challenges we face.

Laparoscopic complete mesocolic excision via mesofascial separation for left-sided colon cancer

PURPOSE

To evaluate the safety and feasibility of laparoscopic complete mesocolic excision (CME) via mesofascial separation for left-sided colon cancer.

METHODS

We evaluated prospectively collected data on 65 consecutive patients with stage I-III left-sided colon cancer, who underwent laparoscopic CME between October 2011 and September 2016. After the exclusion of 5 patients who had T4b or other active tumors, 60 patients were the subjects of this analysis. The completeness of CME, preservation of the hypogastric nerve, operative data, pathological findings, complications, and length of hospital stay were assessed.

RESULTS

CME completeness was graded as the mesocolic and intramesocolic plane in 54 and 6 patients, respectively. The hypogastric nerve was preserved in all patients. A total of 17, 12, 28, and 3 patients had T1, T2, T3, and T4a tumors, respectively. The mean number of lymph nodes retrieved was 16.2, and lymph node metastasis was identified in 22 patients. The mean operative time and intraoperative blood loss were 283 min and 38 ml, respectively. One patient had an intraoperative complication and six patients had postoperative complications. The hospital stay was 12 days.

CONCLUSION

Laparoscopic CME via mesofascial separation is a safe and feasible procedure for left-sided colon 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.

[Spleen tyrosine kinase inhibits proliferation and promotes apoptosis of colorectal cancer cells in vitro via regulating Fra-1]

OBJECTIVE

To investigate the effects of spleen tyrosine kinase (SYK) overexpression on proliferation and apoptosis of colorectal cancer cells and explore the possible mechanism.

METHODS

The mRNA expressions of SYK and Fra?1 in 10 clinical specimens of colorectal cancer and 10 adjacent tissues were measured with qRT?PCR, and their protein expressions were detected with Western blotting. The recombinant plasmid pcDNA.3.1?SYK was constructed and transfected into colorectal cancer cells to induce SYK overexpression, and the cell viability and proliferation were assessed using by MTT assay and BrdU assay, respectively; caspase?3 activity in the cells was evaluated with a commercial kit and the cell apoptosis was analyzed with Annexin?V FITC/PI assay.

RESULTS

The expressions of SYK were significantly decreased in colorectal cancer tissues and colorectal cancer cell lines. Transfection of pcDNA.3.1?SYK into the colorectal cancer cells induced obviously upregulated mRNA and protein expressions of SYK, which caused a significant suppression of the cell viability and proliferation and enhancement of the cell apoptosis along with a significant inhibition of Fra?1 expression.

CONCLUSION

s SYK overexpression inhibits the proliferation and promotes apoptosis of colorectal cancer cells, and these effects are possibly mediated by the regulation of Fra?1 expression by SYK.

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

AIM

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

METHOD

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

RESULTS

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

CONCLUSION

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

Robotic right colectomy with intracorporeal anastomosis for malignancy

Techniques for robotic resection of the right colon have not been extensively published or adopted. We report our initial experience of robotic right colectomy with intracorporeal anastomosis and specimen extraction through a Pfannenstiel incision retrospectively. Twenty-one consecutive patients with a right colon cancer (n = 18) or polyp too large to remove endoscopically (n = 3) were treated at Mayo Clinic Rochester, Minnesota. Main outcomes measured were estimated blood loss, operative time, conversion rate, return of gastrointestinal function, length of stay, overall and severe complications, discharge status, and pathology. All 21 procedures were technically successful without the need for conversion. The mean total operative time was 250 ± 56 min, estimated blood loss was less than 100 mL in 19 (90%), only 1 (5%) ileus occurred, mean length of stay and return of gastrointestinal function was 4 ± 1.3 and 1 ± 0.6 days, respectively, only 1 (5%) patient experienced a Dindo grade ≥ 3 complication, and 20 (95%) were discharged to home. Mean number of nodes resected was 26 ± 12. Tumors were diagnosed as stage 0 in 3 (14%), stage I in 7 (33%), stage II in 4 (19%), stage III in 6 (28%), and stage IV in 1 (5%). Main limitations were nonrandomized nature, single institution experience, small patient sample size, and procedures only being performed by two surgeons. Finally, we conclude that robotic right colectomy with central mesocolic excision, intracorporeal anastomosis, and extraction through a Pfannenstiel incision is technically feasible, efficacious, oncologically acceptable, and safe to perform.

Is complete mesocolic excision oncologically superior to conventional surgery for colon cancer? A retrospective comparative study

Background:

During the last decade, many efforts have been made in order to improve the oncologic outcomes following colonic resection. Complete mesocolic excision (CME) has proved to provide high rates of disease-free and overall survival rates in patients undergoing resection for colonic malignancies. The aim of our study was to further investigate the role of CME in colonic surgery through comparison with a series of conventional resections.

Methods:

All data regarding resections for colonic cancer since 2006 were obtained prospectively from two surgical departments. Retrieved data from 290 patients were analyzed and compared between those who underwent CME and those who had conventional surgery.

Results:

The CME group presented a higher rate of postoperative morbidity and readmissions. Histopathological features were in favor of CME surgery compared with the conventional group, in terms of both resected bowel length (33 vs. 20 cm) and lymph node harvest (27 vs. 18). Although CME was associated with better disease-free and overall survival times, only tumor differentiation, adjuvant chemotherapy and age had a statistically significant affect on those outcome values (P<0.05).

Conclusion:

CME improves histopathologic features, but without presenting oncologic superiority. Larger prospective studies following adequate surgical training are needed to prove the technique’s advantages in oncologic outcomes.

The da Vinci Xi: a review of its capabilities, versatility, and potential role in robotic colorectal surgery

The Xi is the latest da Vinci surgical system approved for use in colorectal surgery. With its novel overhead architecture, slimmer boom-mounted arms, extended instrument reach, guided targeting, and integrated auxiliary technology, the Xi manages to address several limitations of earlier models. The versatility of this new system allows it to be implemented in a wide range of colorectal procedures - from complex multiquadrant colectomies to challenging mesorectal dissections in the pelvis. While commonly criticized for its cost and prolonged operative time, robotic colorectal surgery holds the potential for enhanced ergonomics, superior precision, and a reduction in the learning curve involved in training an expert surgeon. This review appraises the existing literature on robotic colorectal surgery while elaborating how the improved capabilities of the Xi serve to usher in a new era of minimally invasive colorectal surgery.

Population-based study to re-evaluate optimal lymph node yield in colonic cancer

BACKGROUND

It is well established that lymph node (LN) yield in colonic cancer resection has prognostic significance, although optimal numbers are not clear. Here, LN thresholds associated with both LN positivity and survival were evaluated in a single population-based data set.

METHODS

Treatment records were linked to the Ontario Cancer Registry to identify a 25 per cent random sample of all patients with stage II/III colonic cancer between 2002 and 2008. Multivariable regression and Cox models evaluated factors associated with LN positivity and cancer-specific survival (CSS) respectively. Optimal thresholds were obtained using sequential regression analysis.

RESULTS

On adjusted analysis of 5508 eligible patients, younger age (P < 0·001), left-sided tumours (P = 0·003), higher T category (P < 0·001) and greater LN yield (relative risk 0·89, 95 per cent c.i. 0·81 to 0·97; P = 0·007) were associated with a greater likelihood of LN positivity. Regression analyses with multiple thresholds suggested no substantial increase in LN positivity beyond 12-14 LNs. Cox analysis of stage II disease showed that lower LN yield was associated with a significant increase in the risk of death from cancer (CSS hazard ratio range 1·55-1·74; P < 0·001) compared with a greater LN yield, with no significant survival benefit beyond a yield of 20 LNs. Similarly, for stage III disease, a lower LN yield was associated with an increase in the risk of death from cancer (CSS hazard ratio range 1·49-2·20; P < 0·001) versus a large LN yield. In stage III disease, there was no observed LN threshold for survival benefit in the data set.

CONCLUSION

There is incongruity in the optimal LN evaluation for colonic cancer. Although the historically stated threshold of 12 LNs may ensure accurate staging in colonic cancer, thresholds for optimal survival are associated with far greater yields.

Laparoscopic complete mesocolic excision via combined medial and cranial approaches for transverse colon cancer

PURPOSE

To evaluate the safety and feasibility of laparoscopic complete mesocolic excision via combined medial and cranial approaches with three-dimensional visualization around the gastrocolic trunk and middle colic vessels for transverse colon cancer.

METHODS

We evaluated prospectively collected data of 30 consecutive patients who underwent laparoscopic complete mesocolic excision between January 2010 and December 2015, 6 of whom we excluded, leaving 24 for the analysis. We assessed the completeness of excision, operative data, pathological findings, length of large bowel resected, complications, length of hospital stay, and oncological outcomes.

RESULTS

Complete mesocolic excision completeness was graded as the mesocolic and intramesocolic planes in 21 and 3 patients, respectively. Eleven, two, eight, and three patients had T1, T2, T3, and T4a tumors, respectively; none had lymph node metastases. A mean of 18.3 lymph nodes was retrieved, and a mean of 5.4 lymph nodes was retrieved around the origin of the MCV. The mean large bowel length was 21.9 cm, operative time 274 min, intraoperative blood loss 41 mL, and length of hospital stay 15 days. There were no intraoperative and two postoperative complications.

CONCLUSION

Our procedure for laparoscopic complete mesocolic excision via combined medial and cranial approaches is safe and feasible for transverse colon cancer.