Efficacy and safety of endoscopic submucosal dissection for papillary adenocarcinoma-type early gastric cancer

Endoscopic submucosal dissection (ESD) has increasingly been used to treat early gastric cancer (EGC); however, its efficacy in treating papillary adenocarcinoma-type EGC remains unknown. We sought to identify risk factors for lymph node (LN) metastasis in papillary adenocarcinoma-type EGC and evaluate the clinical outcome after ESD. This study retrospectively reviewed the medical records of patients who were diagnosed with EGC in our hospital from January 2009 to December 2016. In total, 85 patients had papillary adenocarcinoma-type EGC, of whom 52 and 33 underwent surgical treatment and ESD, respectively. This study analyzed the LN metastasis risk factors and clinical outcomes between these 2 groups and with those of an existing ESD indication group. LN metastasis occurred in 13 (25.0%) of 52 patients who underwent surgery. Multivariate analysis indicated that lymphovascular invasion was an independent risk factor (odds ratio: 20.624; 95% confidence interval: 19.628-21.497; P=.001). Of 33 patients who underwent ESD, 21 (63.6%) had an absolute indication and 12 (36.4%) had an expanded indication. All 3 (9.1%) patients with non-curative resection underwent additional surgery. The clinical outcomes were compared to those of 926 patients who underwent ESD of non-papillary adenocarcinoma-type EGC. There were no significant differences in curative resection rate (P=.327), procedure-related complication (P=.853), local recurrence (P=1.000), or overall survival (P=1.000). ESD of papillary adenocarcinoma-type EGC showed an acceptable outcome in comparison to an existing ESD indication group. However, these patients exhibit a relatively higher risk of LN metastasis.