Early detection of gastric cancer is crucial because the survival rate can be improved through curative treatment. Although surgery and gastrectomy with lymph node dissection remain as the gold standard for curative treatment, early gastric cancer (EGC) with negligible risk of lymph node metastasis can be treated with endoscopic resection (ER), such as endoscopic submucosal dissection. Among gastric cancers, undifferentiated-type cancer is distinguished from differentiated-type cancer in various aspects in terms of clinical features and pathophysiology. The undifferentiated-type cancer is also known to be associated with an aggressive behavior and a poor prognosis. Therefore, the indication of ER for undifferentiated EGC is limited compared with differentiated-type. Recent studies have reported that ER for undifferentiated EGC is safe and shows favorable short- and long-term outcomes. However, it is necessary to understand the details of the research results and to selectively accept them. In this review, we aimed to evaluate the current practice guidelines and the short-term and long-term outcomes of ER for undifferentiated type EGC.

中文翻译：

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未分化型早期胃癌的内镜切除术

早期发现胃癌至关重要，因为通过治愈性治疗可以提高存活率。尽管手术和胃切除联合淋巴结清扫仍然是治愈性治疗的金标准，但淋巴结转移风险可忽略的早期胃癌 (EGC) 可以通过内镜切除术 (ER) 进行治疗，例如内镜粘膜下切除术。在胃癌中，未分化型癌与分化型癌在临床特征和病理生理学上有不同的区别。还已知未分化型癌症与攻击行为和不良预后有关。因此，与分化型相比，未分化型 EGC 的 ER 指征是有限的。最近的研究表明，未分化 EGC 的 ER 是安全的，并显示出良好的短期和长期结果。但是，需要了解研究结果的细节并有选择地接受它们。在本综述中，我们旨在评估当前的实践指南以及 ER 对未分化型 EGC 的短期和长期结果。