Nishiwaki Noriyuki, Irino Tomoyuki, Fujiya Keiichi, Kamiya Satoshi, Hikage Makoto, Tanizawa Yutaka, Bando Etsuro, Kusafuka Kimihide, Terashima Masanori
Division of Gastric Surgery, Shizuoka Cancer Center, Shizuoka, Japan; Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Japan.
Division of Gastric Surgery, Shizuoka Cancer Center, Shizuoka, Japan; Department of Surgery, School of Medicine, Keio University, Tokyo, Japan.
Eur J Surg Oncol. 2021 May;47(5):1055-1061. doi: 10.1016/j.ejso.2020.10.023. Epub 2020 Oct 23.
Extra-nodal metastasis (ENM) is defined as a tumor nodule without histological evidence of a lymph node structure. Although ENM has pathological features distinct from those of metastatic lymph nodes, both ENM and metastatic lymph nodes are considered within the same category in the pathological nodal (pN) classification. This study aimed to clarify the clinicopathological characteristics and prognostic relevance of ENM in gastric cancer patients who underwent curative gastrectomy.
We retrospectively evaluated 1207 Japanese patients who underwent curative gastrectomy at a single center between January 2009 and December 2013. All resected specimens were fixed in 10% formalin, processed, and stained using hematoxylin and eosin, and subsequently reviewed by two pathologists. Survival times were analyzed using the Kaplan-Meier method, and independent prognostic factors were identified using a Cox proportional hazards regression model.
Patients who were ENM-positive had significantly poorer overall survival; multivariable analysis revealed that independent prognostic factors were older age (hazard ratio [HR]: 3.68, 95% confidence interval [CI]: 2.60-5.20), higher pathological tumor classification (HR: 2.28, 95% CI: 1.43-3.62), presence of metastatic lymph nodes (HR: 1.57, 95% CI: 1.0-2.36), and ENM-positive status (HR: 2.33, 95% CI: 1.48-3.66). ENM-positive patients had similar survival outcomes to those of ENM-negative patients with ≥16 metastatic lymph nodes.
Among Japanese patients with gastric cancer who underwent curative gastrectomy, ENM was an independent prognostic factor with a prognostic significance different from that of lymph node metastasis. These results suggest that ENM and lymph node metastasis should be classified separately.
结外转移（ENM）被定义为无淋巴结结构组织学证据的肿瘤结节。尽管ENM具有与转移性淋巴结不同的病理特征，但在病理淋巴结（pN）分类中，ENM和转移性淋巴结都被归为同一类别。本研究旨在阐明接受根治性胃切除术的胃癌患者中ENM的临床病理特征及预后相关性。
我们回顾性评估了2009年1月至2013年12月期间在单一中心接受根治性胃切除术的1207例日本患者。所有切除标本均用10%福尔马林固定、处理，并用苏木精和伊红染色，随后由两名病理学家进行复查。采用Kaplan-Meier法分析生存时间，并用Cox比例风险回归模型确定独立预后因素。
ENM阳性患者的总生存期明显较差；多变量分析显示，独立预后因素为年龄较大（风险比[HR]：3.68，95%置信区间[CI]：2.60-5.20）、病理肿瘤分级较高（HR：2.28，95%CI：1.43-3.62）、存在转移性淋巴结（HR：1.57，95%CI：1.0-2.36）以及ENM阳性状态（HR：2.33，95%CI：1.48-3.66）。ENM阳性患者与有≥16个转移性淋巴结的ENM阴性患者的生存结果相似。
在接受根治性胃切除术的日本胃癌患者中，ENM是一个独立的预后因素，其预后意义与淋巴结转移不同。这些结果表明，ENM和淋巴结转移应分别分类。
