Regional Lymph Node Dissection as an Additional Treatment Option to Endoscopic Resection for Expanded Indications in Gastric Cancer: a Prospective Cohort Study

Abstract

Purpose: Expanded indications for endoscopic submucosal dissection (ESD) in early gastric cancer (EGC) remain controversial due to the potential risk of undertreatment after adequate lymph node dissection (LND). Regional LND (RLND) is a novel technique used for limited lymphadenectomy to avoid gastrectomy. This study established the safety and effectiveness of RNLD as an additional treatment option after ESD for expanded indications.

Materials and methods: A total of 69 patients who met the expanded indications for ESD were prospectively enrolled from 2014 to 2017. The tumors were localized using intraoperative esophagogastroduodenoscopy (EGD) before RLND. All patients underwent RLND first, followed by conventional radical gastrectomy with LND. The locations of the preoperative and intraoperative EGD were compared. Pathologic findings of the primary lesion and the RLND status were analyzed.

Results: The concordance rates of tumor location between the preoperative and intraoperative EGD were 79.7%, 76.8%, and 63.8% according to the longitudinal, circumferential, and regional locations, respectively. Of the 4 patients (5.7%) with metastatic LNs, 3 were pathologically classified as beyond the expanded indication for ESD and 1 had a single LN metastasis in the regional lymph node.

Conclusions: RLND is a safe additional option for the treatment of EGC in patients meeting expanded indications after ESD.

Keywords: Endoscopic mucosal resection; Endoscopy; Minimally invasive surgical procedures; Regional lymph node dissection; Stomach neoplasms.

Fig. 1. Definition of 9 regions and station of regional lymph node according to the tumor location.

Fig. 2. Flow chart of the study protocol.

EGD = esophagogastroduodenoscopy; CT = computed tomography; LN = lymph node.

Fig. 3. Concordance status between pre- and intraoperative EGD.

EGD = esophagogastroduodenoscopy; LC = lesser curvature; GC = greater curvature; AW = anterior wall; PW = posterior wall; ULC = upper lesser curvature; UAP = upper anterior to posterior; UGC = upper greater curvature; MLC = middle lesser curvature; MAP = middle anterior to posterior; MGC = middle greater curvature; LLC = lower lesser curvature; LAP = lower anterior to posterior; LGC = lower greater curvature.