Barreto Savio G, Windsor John A
Department of Gastrointestinal Surgery, Gastrointestinal Oncology, and Bariatric Surgery, Medanta Institute of Digestive and Hepatobiliary Sciences, Medanta, The Medicity, Gurgaon, India.
HBP/Upper GI Unit, Department of General Surgery, Auckland City Hospital, Auckland, New Zealand.
Surg Endosc. 2016 Jan;30(1):24-37. doi: 10.1007/s00464-015-4184-z. Epub 2015 Apr 1.
The problem is that current definitions of early gastric cancer allow the inclusion of regional lymph node metastases. The increasing use of endoscopic submucosal dissection to treat early gastric cancer is a concern because regional lymph nodes are not addressed. The aim of the study was thus to critically evaluate current evidence with regard to tumour-specific factors associated with lymph node metastases in "early gastric cancer" to develop a more precise definition and improve clinical management.
A systematic and comprehensive search of major reference databases (MEDLINE, EMBASE, PubMed and the Cochrane Library) was undertaken using a combination of text words "early gastric cancer", "lymph node metastasis", "factors", "endoscopy", "surgery", "lymphadenectomy" "mucosa", "submucosa", "lymphovascular invasion", "differentiated", "undifferentiated" and "ulcer". All available publications that described tumour-related factors associated with lymph node metastases in early gastric cancer were included.
The initial search yielded 1494 studies, of which 42 studies were included in the final analysis. Over time, the definition of early gastric cancer has broadened and the indications for endoscopic treatment have widened. The mean frequency of lymph node metastases increased on the basis of depth of infiltration (mucosa 6% vs. submucosa 28%), presence of lymphovascular invasion (absence 9% vs. presence 53%), tumour differentiation (differentiated 13% vs. undifferentiated 34%) and macroscopic type (elevated 13% vs. flat 26%) and tumour diameter (≤2 cm 8% vs. >2 cm 25%).
There is a need to re-examine the diagnosis and staging of early gastric cancer to ensure that patients with one or more identifiable risk factor for lymph node metastases are not denied appropriate chemotherapy and surgical resection.
问题在于目前早期胃癌的定义允许纳入区域淋巴结转移情况。由于未处理区域淋巴结，内镜下黏膜下剥离术在早期胃癌治疗中的应用日益增加令人担忧。因此，本研究的目的是严格评估当前关于“早期胃癌”中与淋巴结转移相关的肿瘤特异性因素的证据，以制定更精确的定义并改善临床管理。
使用“早期胃癌”“淋巴结转移”“因素”“内镜检查”“手术”“淋巴结清扫术”“黏膜”“黏膜下层”“淋巴管侵犯”“分化型”“未分化型”和“溃疡”等文本词组合，对主要参考文献数据库（MEDLINE、EMBASE、PubMed和Cochrane图书馆）进行系统全面的检索。纳入所有描述早期胃癌中与淋巴结转移相关的肿瘤相关因素的现有出版物。
初步检索得到1494项研究，其中42项研究纳入最终分析。随着时间推移，早期胃癌的定义不断扩大，内镜治疗的适应证也在拓宽。基于浸润深度（黏膜层6% vs. 黏膜下层28%）、淋巴管侵犯情况（无9% vs. 有53%）、肿瘤分化程度（分化型13% vs. 未分化型34%）、大体类型（隆起型13% vs. 平坦型26%）和肿瘤直径（≤2 cm 8% vs. >2 cm 25%），淋巴结转移的平均发生率有所增加。
有必要重新审视早期胃癌的诊断和分期，以确保具有一个或多个可识别的淋巴结转移危险因素的患者不会被剥夺适当的化疗和手术切除机会。
