The short- and long-term outcomes of laparoscopic D2 lymphadenectomy plus complete mesogastrium excision for lymph node-negative gastric cancer

BACKGROUND

Patients with T1-3N0M0 gastric cancer (GC) who undergo radical gastrectomy maintain a high recurrence rate. The free cancer cells in the mesogastric adipose connective tissue (Metastasis V) maybe the reason for recurrence in these individuals. We aimed to evaluate whether D2 lymphadenectomy plus complete mesogastrium excision (D2 + CME) was superior to D2 lymphadenectomy with regard to safety and oncological efficacy for T1-3N0M0 GC.

METHODS

Patients with T1-3N0M0 GC who underwent radical resection from January 2014 to July 2018 were retrospectively analyzed; there were 323 patients, of whom 185 were in the D2 + CME group and 138 in the D2 group. The primary endpoint was 5-year disease-free survival (DFS). Secondary endpoints include the 5-year overall survival (OS), recurrence pattern, morbidity, mortality, and surgical outcomes.

RESULTS

D2 + CME was associated with less intraoperative bleeding loss, a greater number of lymph nodes harvested, and less time to first postoperative flatus, but the postoperative morbidity was similar. The 5-year DFS was 95.6% (95% CI 92.7-98.5%) and 90.4% (95% CI 85.5-95.3%) in the D2 + CME group and the D2 group, respectively, with a hazard ratio (HR) of 0.455 (95% CI 0.188-1.097; p = 0.071). In terms of recurrence patterns, local recurrence was more prone to occur in the D2 group (p = 0.031). Subgroup analysis indicated that for patients with T1b-3N0M0 GC, the 5-year DFS in the D2 + CME group was considerably greater than that in the D2 group (95.3% [95% CI 91.6-99.0%] vs. 87.6% [95% CI 80.7-94.5%], HR 0.369, 95% CI 0.138-0.983; log-rank p = 0.043).

CONCLUSION

Laparoscopic D2 + CME for T1-3N0M0 GC is safe and feasible. Furthermore, it not only reduces the local recurrence rate but also improves the 5-year DFS in cases of T1b-3N0M0 GC.

[Radical surgery for colon cancer guided by membrane anatomy theory]

Like other solid tumors, colon cancer surgery has undergone a century-old journey from lumpectomy to organ resection and then to lymphadenectomy. From the Toldt fascia to complete mesenteric resection, and from local resection to D3 radical treatment, local recurrence rates have been reduced, but remain a nuisance to surgeons and patients. Based on the theory of membrane anatomy, radical surgery for colon cancer will focus more on removing the mesocolon from the mesentery bed while maintaining the integrity of the posterior fascia to avoid the occurrence of "fifth metastasis" as much as possible. Thanks to the membrane anatomy theory, its strong reproducibility and replicability, a new phase of colorectal surgery is on the horizon.

Detection of metastatic cancer cells in mesentery of colorectal cancer patients

AIM

To detect the existence of isolated cancer cells in the mesentery of colorectum (named as Metastasis V), and investigate its clinical significance in colorectal cancer (CRC) patients.

METHODS

Sixty-three CRC patients who received radical excision between January 2012 and September 2015 were included. All the patients underwent laparoscopy-assisted radical colorectomy or proctectomy [with complete mesocolic excision (CME) or total mesorectal excision (TME)] with R0 dissections at the Department of Gastrointestinal Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology. The location and size of the primary lesions were recorded immediately after the tumor was removed, with the surrounding mesenterium completely separated along the intestinal wall. Each dissected mesentery sample was analyzed for hematoxylin-eosin staining and immunohistochemistry using cytokeratin 19 antibody. Image Pro Plus Software 6.0 (Media Cybernetics, CA, United States) was used to semi-quantitatively measure the concentration of the cytokeratin 19 immunohistochemistry. The correlation between metastasis found in mesentery and clinicopathological characteristics was examined. The prognosis of patients was also evaluated by preoperative serum CEA level.

RESULTS

Metastasis V was detected in 14 of 63 (22.2%) CRC patients who underwent laparoscopy-assisted radical colorectomy or proctectomy (with CME or TME) with R0 dissection in our hospital between January 2012 and September 2015. There was no significant difference in age, gender, tumor size, and tumor location in patients with Metastasis V (P > 0.05). Metastasis V was more likely to occur in poorly differentiated tumor (5/11; 45.5%) than moderately (8/46; 17.4%) and well- differentiated one (1/6; 16.7%). The Metastasis V in N2 stage (9/14; 64.3%) was more frequent that in the N0 stage (3/35; 8.6%) or N1 stages (2/14; 14.3%). In addition, Metastasis V was positively related to the tumor invasive depth (T1:0/1, 0%; T2:1/12, 8.3%; T3:7/39, 17.9%; T4:6/11, 54.5%). Furthermore, preoperative serum CEA level in Metastasis V-positive patients was significantly higher than in Metastasis V-negative patients (4.27 ng/mL vs 3.00 ng/mL).

CONCLUSION

Metastasis V might be associated with a poor prognosis of CRC patients.