Complete mesocolic excision and extended lymphadenectomy: Where should we stand?

Debate regarding the risks and merits of complete mesocolic excision and extended lymphadenectomy is ongoing, particularly for right-sided colon cancers. In this article, we hope to provide a succinct yet encompassing review of the relevant literature. We posit that complete mesocolic excision with D3 dissection is indicated in select patients with colon cancers, particularly those distal to the cecum.

Study protocol for an International Prospective Observational Cohort Study for Optimal Bowel Resection Extent and Central Radicality for Colon Cancer (T-REX study).

This is a prospective observational cohort study aiming to include 4000 patients with stages I to III colon cancer treated at 35 specialist institutions in Japan, South Korea, Germany, Russia, Lithuania and Taiwan. The anatomical distribution of lymph nodes and feeding arteries are investigated using surgical specimens according to pre-specified categorizing methods using intraoperative anatomical markings. Primary analyses are performed to identify the general principles of metastatic lymph node distribution in terms of its relation to the location of the primary tumor and feeding arteries. Secondary analyses will be used to estimate prognostic outcomes according to bowel resection length and central radicality and will be used to evaluate the quality of resected surgical specimens. Through in-depth lymph node mapping, standardized criteria for the definite area of 'regional' lymph node resection in routine surgical procedures can be identified, which is expected to contribute to international standardization in colon cancer surgery (ClinicalTrials.gov NCT02938481).

Improved oncologic outcomes with increase of laparoscopic surgery in modified complete mesocolic excision with D3 lymph node dissection for T3/4a colon cancer: results of 1191 consecutive patients during a 10-year period: a retrospective cohort study.

BACKGROUND: Laparoscopic modified complete mesocolic excision (mCME) with D3 lymph node dissection has been performed with increasing frequency, but the oncological safety remains unclear. This study investigated the oncological safety of laparoscopic modified CME with D3 dissection for pT3/4a M0 colon cancer. PATIENTS: Consecutive patients with pT3/4a M0 colon cancer undergoing curative colectomy at a comprehensive cancer center between 2004 and 2013 were included. Outcomes were compared between early (2004-2008, n = 450) and late (2009-2014, n = 741) periods. Prognostic factors were investigated by multivariate analysis. RESULTS: A total of 1191 patients were eligible. Median follow-up was 57 months. Laparoscopic surgeries were more common in the late period (early vs late: 53.6% vs. 91.8%, p < 0.01). Patients in the late period showed lower blood loss (20 mL vs. 10 mL, p < 0.01), higher number of harvested lymph nodes (18.1 vs. 21.6, p < 0.01) and fewer patients with < 12 harvested nodes (13.6% vs. 5.8%, p < 0.01). Postoperative complication rates were similar between periods (2.7% vs. 2.7%, p = 0.97). Five-year relapse-free survival rate (RFS) (75.3% vs. 82.7%, p < 0.01) and overall survival rate (OS) (86.9% vs. 91.7%, p = 0.01) were higher in the late period. Multivariate analysis revealed laparoscopic surgery as an independent favorable prognostic factor for both RFS (hazard ratio (HR) = 0.73, 95% confidence interval (CI) 0.54-0.99, p = 0.03) and OS (HR = 0.56, 95% CI 0.37-0.83, p < 0.01). CONCLUSION: Improved oncologic outcomes and more frequent laparoscopic surgery during the 10-year period of the study were demonstrated for modified CME with D3 dissection, suggesting the safety of this procedure performed by experienced surgeons for pT3/4a M0 colon cancer.

CME versus D3 Dissection for Colon Cancer.

Over the past 30 years, rectal cancer surgery has been standardized by total mesorectal excision. More recently, some have suggested that colon cancer surgery should be standardized by complete mesocolic excision (CME) with central vascular ligation (CVL), especially in Western countries. Surgeons undertaking CME with CVL report optimal outcomes. Sharp dissection within the embryological plane and high vascular ligation at the vessel origin are essential. In Japan, a similar concept, D3 dissection, has been adopted for decades. Although both surgical procedures are similar, distinct differences exist. Some surgeons are confused about the principles and practice of these two procedures. As well as overviewing the theory behind CME with CVL and D3 dissection, the technical details of both procedures are described.

[Short-term outcomes of complete mesocolic excision for right colon cancer]. / Neposredstvennye rezul'taty pravostoronnei gemikoléktomii s total'noi mezokolonéktomiei i D3 limfodissektsiei pri lechenii raka pravoi poloviny obodochnoi kishki.

PURPOSE: Complete mesocolic excision (CME) appears to be a relatively new concept for colon cancer. The purpose is to evaluate the results of CME with high vascular ligation (D3 lymph node dissection) for right colon cancer. The presented study identifies possible risks and advantages of the proposed method, as well as the role of the laparoscopic approach. MATERIAL AND METHODS: The article included data from 39 patients with right colon cancer, TNM stage I-III, operated on between November 2015 and December 2016 in the oncoproctology Department of the Blokhin Cancer Research Center. The analysis of main intraoperative parameters, morbidity and mortality was carried out. RESULTS: There was no postoperative mortality. 17 (43.6%) of operations were performed by open and 22 - by laparoscopic approach. The conversion for laparoscopic approach was 1 (4.5%) in 22. The median duration of the operation was 180 (130-260) minutes for laparoscopic approach and 120 (90-280) minutes for open approach, р=0.0056. Median intraoperative blood loss was 30 (30-300) ml for laparoscopic approach, and 300 (30-500) ml for open approach (р=0.0001). The duration of lymphorrhoea, time to first bowel movement, time to start liquid and solid food intake were 5.1±2.4, 1.3±0.5, 1.26±0.4 and 3.2±0.7 days, respectively. The median number of removed lymph nodes was 35.7 (6-68), the median number of metastatic lymph nodes was 1.9 (0-16). The median number of removed apical lymph nodes was 10.3 (0-24). Metastases did not affect any of the lymph nodes of the apical group. CONCLUSION: Right mesocolic excision with D3 lymphadenectomy for right colon cancer is technically safe, and the laparoscopic approach provides all the benefits of minimally invasive surgery and excellent early treatment outcomes. Preliminary data shows no metastasis in apical lymphnodes for right colon cancer. Nonetheless, it is necessary to study the long-term results for the evaluation of oncological outcomes.

Surgical and oncological outcome after extended lymph node dissection for carcinoma of the stomach and the esophagogastric junction: a retrospective analysis from an experienced single center.

Introduction: Gastric cancer remains the fourth leading cause of cancer-related death in Europe, while the proportion of adenocarcinomas of the esophagogastric junction has risen by more than one third over recent years. In 2018, 14,700 new cases of gastric cancer were estimated in Germany, while the 5-year relative survival rate is reported to be 33% for women and 30% for men; in the USA almost the same rate was reported, with 31% 5-year survival. Material and methods: Between 2001 and 2014, 590 patients with a diagnosis of gastric cancer underwent surgery in our institution, including 120 Siewert type II/III carcinomas of the esophagogastric junction. All patients underwent distal resection of the stomach, gastrectomy or total gastrectomy combined with transhiatal distal esophageal resection. All operations included D2-D3 lymph node dissection (LND). Data were recorded by the cancer registry of the department of surgery and analyzed retrospectively. Results: The patients were classified according to the TNM (UICC 2010) and Lauren classification. 29% of the patients underwent primary surgery and 31% received neoadjuvant therapy. The median number of harvested lymph nodes was 33 for patients diagnosed with gastric cancer, and 29 for esophagogastric adenocarcinomas, respectively. The anastomotic leak rate was 3%. In this study, the 5-year overall survival rate was 51% concerning gastric carcinomas, 44% for Siewert type II and 47% for Siewert III cancers of the esophagogastric junction. Conclusions: Increased survival with low complication rates were achieved after individualized and multimodal treatment concepts combined with consistently applied extended lymphadenectomy.

Current standards of lymphadenectomy in gastric cancer.

Gastric cancer remains the 5th most common cancer and the 3rd most common cause of cancer mortality. Most patients diagnosed with gastric cancer still have a poor prognosis due to its advanced presentation at diagnosis, even in countries with developed screening programs. Surgery is the cornerstone of the treatment for gastric cancer, often combined with perioperative chemotherapy. Lymph node dissection is a crucial component of the surgical treatment of gastric cancer. D1 lymphadenectomy is currently recommended for early stage tumors. The extent of lymphadenectomy in advanced gastric cancer, however, is still a matter of debate between Eastern and Western surgeons. Although a D2 dissection is the current standard recommended by most guidelines, there might be a place for more limited dissections such as D1 + in selected cases. This evidence-based review will help defining the optimal lymphadenectomy for patients with gastric cancer.

Complete Mesocolic Excision and Extent of Lymphadenectomy for the Treatment of Colon Cancer.

Curative-intent surgical resection of colon cancer involves optimal approaches to the peri-tumoral tissue, the mesocolon, and the draining lymph nodes. The key corresponding concepts that will be discussed are complete mesocolic excision (CME), central vascular ligation (CVL) or D3 dissection, and circumferential resection margin (CRM). We aim to describe these techniques and delineate evidence surrounding their technical feasibility, pathologic detail, as well as long-term oncologic impact. CME with CVL and D3 dissection are overlapping concepts both emphasizing anatomy-based resection of tumor and regional lymph nodes that does not breach the embryonic visceral fascia and ensures complete lymph node dissection up to the mesenteric root. Completeness of the mesocolic plane, number of harvested nodes, and CRM are surgical pathologic parameters that impact oncologic outcome. Attention to these details has been associated with improved outcomes in retrospective observational trials and the choice of open or minimally invasive approaches must be determined by surgeon's technical experiences.

Surgical Outcomes of Laparoscopic and Open D3 Dissection for Clinical Stage II/III Descending Colon Cancer.

AIM: To compare the surgical outcomes of laparoscopic colectomy (LAC) with Japanese D3 dissection for descending colon cancer (DCC) with those of open colectomy (OC). PATIENTS AND METHODS: Seventy-two patients who underwent OC or LAC with D3 dissection for clinical stage II/III DCC between September 2002 and June 2019 were evaluated in terms of short-term outcomes. The long-term outcomes of the 59 patients who underwent surgery between September 2002 and June 2016 were evaluated. RESULTS: Twenty-six patients underwent OC and 46 patients underwent LAC. The blood loss was significantly less in the LAC group. The complication rate was similar in both groups. The rates of 5-year overall survival (95.8% in the OC group vs. 89.9% in the LAC group) and relapse-free survival (79.2% in the OC group vs. 82.1% in the LAC group) were similar in both groups. CONCLUSION: LAC is an acceptable treatment option for stage II/III DCC.

Long-term outcomes of laparoscopic versus open D3 dissection for stage II/III colon cancer: Results of propensity score analyses.

BACKGROUND: Non-inferiority of the laparoscopic approach for stage II/III colon cancer has not been clearly established. This study aimed to evaluate the long-term outcomes of laparoscopic versus open D3 surgery. METHODS: Subjects were 1230 consecutive patients with stage II/III colon cancer, who were referred to the National Cancer Center Hospital from 2004 to 2013. Open surgery was performed in 821 (67%) patients, and laparoscopic surgery was performed in 409 (33%). Propensity score analyses with overall survival as the primary endpoint were performed in three different propensity score methods. RESULTS: Regression adjustment using the propensity score as a linear predictor in the model showed similar overall survival between laparoscopic and open surgeries [hazard ratio (HR), 0.98 (95% CI [0.64-1.46]; p = 0.916)]. Stratification analysis of the entire cohort revealed that, among five strata, only the highest stratum (clinical T2/T3, clinical N0/N1, tumor size <6 cm, and body mass index (BMI) < 28) had an HR of <1 (0.37). In the other four strata, open surgery was favored as reflected by HRs of >1 (1.13-1.26). The propensity score-matched cohort (365 matched pairs), from which patients with advanced disease and high BMI were excluded, yielded an HR of 0.93 (95% CI [0.57-1.52]; p = 0.772). CONCLUSIONS: Laparoscopic surgery appeared to be a safe and reasonable option for patients with stage II/III colon cancer in general. Patients with high BMI, clinical N2 and T4 disease, and tumor size ≥6 cm might require prudent selection of surgical approach.