Shim Choong Nam, Chung Hyunsoo, Park Jun Chul, Lee Hyuk, Shin Sung Kwan, Lee Sang Kil, Lee Yong Chan
Department of Internal Medicine, Institute of Gastroenterology, Yonsei University College of Medicine, 50 Yonsei-ro, Seodaemun-gu, Seoul, 120-752, Korea,
Surg Endosc. 2015 Jul;29(7):1787-94. doi: 10.1007/s00464-014-3861-7. Epub 2014 Oct 3.
Safety of endoscopic resection (ER) for early gastric cancers (EGC) with mixed histology predominantly of differentiated type has not been securely established, since those lesions tend to exhibit lymph node metastasis, compared to pure differentiated type. The purpose of this study was to evaluate clinicopathologic characteristics, therapeutic outcomes, and risk for lymph node metastasis in predominantly differentiated mixed EGC treated by ER.
A total of 1,016 patients with 1,039 EGCs underwent ER between January 2007 and June 2013. Enrolled lesions were divided into groups of either pure differentiated (n = 1,011) or predominantly differentiated mixed (n = 28), according to the presence of mixed histology predominantly of differentiated type in ER specimen.
Mixed histology predominantly of differentiated type was diagnosed in 2.7% of lesions. Larger size, mid-third location, and moderately differentiated histology on forceps biopsy were independent risk factors for the predominantly differentiated mixed histologic type of EGC in multivariate analysis. En bloc resection rate tended to be lower, and complete and curative resection rates were significantly lower in the predominantly differentiated mixed group. The rate of lymph node metastasis in the lesions with additional operation tended to be higher, in this mixed histology group.
Larger size, mid-third location, and moderately differentiated histology on forceps biopsy carry the significant risk for mixed histology predominantly of differentiated type. EGC with predominantly differentiated mixed histologic type affects therapeutic outcomes and consequent clinical course accompanied by possibly higher risk for lymph node metastasis. The safety of ER for predominantly differentiated mixed EGC should be validated by further prospective investigation.
早期胃癌（EGC）若组织学类型主要为分化型且伴有混合型，其内镜下切除术（ER）的安全性尚未得到确切证实，因为相较于单纯分化型病变，这些病变更易发生淋巴结转移。本研究旨在评估经ER治疗的主要为分化型混合性EGC的临床病理特征、治疗效果及淋巴结转移风险。
2007年1月至2013年6月期间，共有1016例患有1039处EGC的患者接受了ER治疗。根据ER标本中是否存在主要为分化型的混合组织学类型，将纳入的病变分为单纯分化型（n = 1011）或主要为分化型混合性（n = 28）两组。
2.7%的病变被诊断为主要为分化型的混合组织学类型。在多因素分析中，较大的尺寸、中三分之一部位以及钳取活检时为中度分化组织学是主要为分化型混合组织学类型EGC的独立危险因素。主要为分化型混合性组的整块切除率往往较低，完整切除率和根治性切除率显著较低。在这一混合组织学类型组中，接受额外手术的病变的淋巴结转移率往往较高。
较大的尺寸、中三分之一部位以及钳取活检时为中度分化组织学是主要为分化型混合组织学类型的显著危险因素。主要为分化型混合组织学类型的EGC会影响治疗效果及后续临床病程，且可能伴有较高的淋巴结转移风险。主要为分化型混合性EGC的ER安全性应通过进一步的前瞻性研究加以验证。
