From January 2016 to December 2016, 52 patients with colon cancer underwent a potentially curative CME with CVL colectomy (CME group) at the Division of Surgical Oncology, Department of Abdominal Oncology, Istituto Nazionale Tumori Fondazione G. Pascale-IRCCS, Naples, Italy, and their cases were prospectively analyzed. The results for this group were compared with the results for another group, including 79 patients who underwent a potentially curative classic or conventional colectomy (non-CME group) from June 2012 to November 2015 at the Surgical Oncology Unit, Oncology Center, Mansoura University, Mansoura, Egypt. Approvals were obtained from the local ethical committees at both the University of Mansoura and the National Cancer Institute at Naples in accordance with Egyptian and Italian bioethics laws in concordance with the Helsinki Declaration Principals. The study was registered in ClinicalTrials.gov with the identifier NCT02526836.

This comparison aimed to evaluate the possible oncological advantages of a CME with regards to qualitative markers (number of harvested lymph nodes, lymph node ratio [LNR]), as well as the morbidity and the mortality rates. Patients who met the following criteria were selected: age between 20 and 80 years; adequate organ function, including liver and cardiovascular functions; pathologically proven adenocarcinoma or adenosquamous carcinoma on endoscopic biopsy; tumor located in the caecum, ascending, transverse, descending, sigmoid or rectosigmoid colon on preoperative endoscopy and radiographic imaging; and provision of written informed consent.

Exclusion criteria were as follows: contraindications to major surgery and American Society of Anesthesiologists physical status classification grade of IV, extreme systemic disorders which have already become an eminent threat to life; history of familial adenomatous polyposis, ulcerative colitis, or Crohn disease; infectious disease that requires treatment; pregnancy; history of psychiatric disease; use of systemic steroids; and history of unstable angina pectoris or myocardial infarction within 6 months. Tumor histopathological classification was applied according to the World Health Organization’s rules [12]. Staging was according to the 7th edition of the TNM classification [13]. Patients with stage III–IV disease received systemic chemotherapy postoperatively.

All colectomies were performed through an open midline laparotomy by the same experienced surgical team in each unit. In the Egyptian experience (non-CME group), the terminal ileum and colon, according to tumor location, were initially severed, and the mesocolon was divided in a V-shape manner at a location that was anatomically convenient. Therefore, ileo-colic vessels, right colic vessels (if present) in the case of right-sided tumors, the trunk of the middle colic vessels in the case of a transverse, extended right or left colectomy, or left colic or inferior mesenteric vessels in the case of left-sided and sigmoid tumors were severed in the mesocolon without identification of their origins. In the Italian experience (CME group), the surgical technique was obviously different [5, 14]. It had 2 components: In the first, a sharp meticulous dissection of the anatomical layers in which the visceral plane was dissected from the parietal one along the Toldt fascia with complete mobilization of the entire mesocolon up to the mesenteric root was performed. The resulting specimen shows the tumor and its lymphatic drainage with no tears in the fascial layers on each side of the mesocolon. In the second component, a central division of the feeding arteries at their origins is performed. For right-side tumors, the division is done at the level of the SMA (Figs. 1, 2) while for left-side tumors, the division is done at the level of the IMA or the aorta (Fig. 3). This allows for removal of the maximum number of lymph nodes possible [6, 15]. Kocher maneuver, as described by Søndenaa et al. [16], though potentially beneficial, was not used. Finally, in both groups, a hand-sewn, side-to-side ileocolic or colocolic anastomosis or a circular stapler anastomosis in the case of sigmoid or rectosigmoid tumors was done.

All patients were discharged from the hospital and received adjuvant chemotherapy in the form of 5-fluorouracil plus oxaliplatin, if needed (pT4, node positive, or metastatic cancers) [17]. The patients’ TNM classifications are presented in Table 1. Additionally, analyses of the lymph node yield, the number of positive lymph nodes, and the LNR, which is the number of positive lymph nodes divided by the total number of removed nodes [18], were done. In addition, tumor location, type of surgical procedure, morbidity, mortality, clinical outcome, and postoperative outcome were recorded.

The extracted data were recorded using Excel spreadsheets under Microsoft Windows (Bristol, UK), and all the statistical analyses were performed using Stata 12 (StataCorp LP., College Station, TX, USA). Categorical variables were reported as numbers and percentages. Continuous variables were described as means ± standard deviations or median and interquartile range according to the distribution. The chi-square test or Fisher exact test was used to compare categorical variables, and the Student t-test or Mann-Whitney U-test was used when appropriate to detect differences between continuous variables. P-values less than 0.05 were considered to indicate statistical significance.

Between June 2010 and November 2015, 79 patients (38 females and 41 males) were admitted to the Surgical Oncology Unit of Mansoura University’s Oncology Center for surgery. As to the locations of the tumors, 20 patients were diagnosed with cecal cancer; in 11 patients, the tumor was located in the ascending colon, in 8, it was located in the hepatic flexure, in 7, it was located in the transverse colon, in 4, it was located in the splenic flexure, in 14, it was located in the descending colon, and in 15, it was located in the sigmoid colon (Table 1). All patients underwent a R0 resection, with 2 patients underwent a nonanatomical liver resection for peripheral hepatic metastasis. The median lymph node yield was 12 (range, 9–16), a significant decrease in comparison to the CME group (median, 22.5; range, 15–30; P < 0.0001), which was reflected in the LNR which had a mean = 0.22, significantly higher than the CME group (0.03; P < 0.0001) (Table 2). After histopathological examination, a moderately differentiated adenocarcinoma was found in 50 patients and a poorly differentiated adenocarcinoma was found in 2 patients.

All patients had elective surgeries: 21 right hemicolectomies, 9 extended right hemicolectomies, 6 left hemicolectomies and 16 sigmoidectomies. No intraoperative adverse events occurred. The average duration of surgery was 135 minutes, and the average intraoperative blood loss was 105 mL. Postoperative complications occurred in two patients. One of them had an anastomotic leakage that was managed conservatively; the other had an incisional hernia and underwent surgery 6 months later. No in-hospital mortality occurred.

Between June 2010 and November 2015, 79 patients (38 females and 41 males) were admitted to the Surgical Oncology Unit of Mansoura University’s Oncology Center for surgery. As to the locations of the tumors, 20 patients were diagnosed with cecal cancer; in 11 patients, the tumor was located in the ascending colon, in 8, it was located in the hepatic flexure, in 7, it was located in the transverse colon, in 4, it was located in the splenic flexure, in 14, it was located in the descending colon, and in 15, it was located in the sigmoid colon (Table 1). All patients underwent a R0 resection, with 2 patients underwent a nonanatomical liver resection for peripheral hepatic metastasis. The median lymph node yield was 12 (range, 9–16), a significant decrease in comparison to the CME group (median, 22.5; range, 15–30; P < 0.0001), which was reflected in the LNR which had a mean = 0.22, significantly higher than the CME group (0.03; P < 0.0001) (Table 2).

All patients underwent elective surgeries: 31 right hemicolectomies, 15 extended right hemicolectomies, 21 left hemicolectomies, 4 extended left hemicolectomies and 8 sigmoidectomies (Figs. 4, 5). On histopathological examination, a well-differentiated adenocarcinoma was found in 3 patients, a moderately differentiated adenocarcinoma in 66, and a poorly differentiated adenocarcinoma in 10. No major intraoperative complications were encountered. The average duration of surgery was higher in comparison with the CME group (180 minutes vs. 135 minutes, P < 0.0001). Also, the intraoperative blood loss was higher (200 mL vs. 105 mL, P < 0.0001). The number of postoperative complications (n = 5) was higher compared to the CME group, but the difference did not reach a statistical significance (P = 0.702). Two patients experienced anastomotic leakage; one of them needed reoperation and the other was managed conservatively. Two patients with postoperative collection were managed conservatively, and one patient who developed an incisional hernia not to undergo surgery to correct it. No in-hospital mortality occurred (Table 2).