The distribution pattern of metastatic lymph nodes after non-curative endoscopic resection in early gastric cancer.

Background And Objectives: Additional surgery should be done after non-curative endoscopic resection (ER) in early gastric cancer (EGC) due to the risk of lymph node metastasis (LNM). However, the distribution pattern of LNM in these patients is complicated and unpredictable. The aim of this study is to identify any different distribution patterns of LNM in patients with EGC who underwent additional surgery after non-curative (ER) comparing to those without ER.

Methods: Patients who underwent surgery for EGC between 2001 and 2016 were included. Enrolled patients were divided into two groups, those who underwent additional surgery after non-curative ER and those who underwent direct surgery without a history of ER. Demographics, tumor characteristics and LNM distribution pattern were analyzed.

Results: Among 4295 patients with EGC, 404 patients had a history of preoperative ER, and 3891 patients did not. After the application of exclusion criteria, 23 (7.1%) of 322 patients undergoing additional surgery had LNM. The additional surgery group showed less LNM, fewer nodal stations and more restricted distribution pattern of LNM.

Conclusions: The distribution pattern of LNM in EGC is complicated. However, more restricted locoregional LNM could be expected in cases of additional surgery after non-curative ER than after direct surgery.