Published online Aug 26, 2020. doi: 10.12998/wjcc.v8.i16.3474
Peer-review started: March 20, 2020
First decision: April 29, 2020
Revised: July 5, 2020
Accepted: July 16, 2020
Article in press: July 16, 2020
Published online: August 26, 2020
Processing time: 158 Days and 0.5 Hours
Endoscopic submucosal dissection (ESD) has become a standard treatment for tumors meeting the specific criteria characteristic of very low lymph node metastasis (LNM) risk: Intramucosal differentiated adenocarcinoma and ≤ 2 cm in size with no ulcers. Meanwhile, in undifferentiated early gastric cancer with a high risk of LNM, gastrectomy with lymph node dissection is usually performed as the standard surgical procedure. For undifferentiated gastric cancer, it consists of mucinous adenocarcinoma, poorly differentiated adenocarcinoma, and primary signet ring cell carcinoma. However, for approximately 96% of surgical patients with early mucinous gastric cancer (EMGC) confined to the mucosa, no LNM was observed, suggesting that it might be over-treated for these cases. Therefore, we have proposed new methods to minimize gastric resection for EMGC. The new technique allows minimally invasive resection of gastric lesions through ESD and laparoscopic sentinel lymph node dissection (SLND).
We attempted to identify a subgroup of EMGC patients in whom the risk of LNM can be ruled out and treated them by ESD and SLND, which may serve as a breakthrough treatment for EMGC.
We carried out this retrospective study to determine the clinicopathological factors that are predictive of LNM in EMGC. Furthermore, we established a simple criterion to expand the possibility of using ESD and SLND for the treatment of EMGC.
The association between the clinicopathological factors and the presence of LNM was retrospectively analyzed by univariate and multivariate logistic regression analyses. Odds ratios (OR) with 95% confidence intervals (CIs) were calculated. We further examined the relationship between the positive number of the three significant predictive factors and the LNM rate.
Depth of invasion (OR = 7.342, 95%CI: 1.127-33.256, P = 0.039), the tumor diameter (OR = 9.158, 95%CI: 1.348-29.133, P = 0.044), and lymphatic vessel involvement (OR = 27.749, 95%CI: 1.821-33.143, P = 0.019) were found to be significant and independent risk factors for LNM by multivariate analysis. For patients with one, two, and three of the risk factors, the LNM rates were 9.1%, 33.3%, and 75.0% respectively. LNM were not found in seven patients without one or more of the three risk factors.
ESD might be a sufficient treatment for intramucosal EMGC if tumor size ≤ 2 cm, and when LVI is absent upon postoperative histological examination. The combination of ESD and SLND could be recommended as an effective, minimally invasive treatment for EMGC patients having a potential risk of LNM.
The minimalization of therapeutic invasiveness in order to preserve quality of life is a major topic in the management of early gastric cancer. One of the critical factors in choosing minimally invasive surgery for EMGC would be the precise prediction of whether the patient has LNM or not. Therefore, in the future, the combination of ESD and SLND could be recommended as an effective, minimally invasive treatment for EMGC patients having a potential risk of LNM.