Huang Lei, Zhang Xinyue, Wei Zhijian, Xu Aman
Department of General Surgery, the First Affiliated Hospital of Anhui Medical University, Hefei, China.
Department of Academic Research, Hefei City First People's Hospital, Hefei, China.
Front Oncol. 2021 Jan 6;10:539030. doi: 10.3389/fonc.2020.539030. eCollection 2020.
While most guidelines advocate D2 lymphadenectomy for non-metastatic gastric adenocarcinoma (nmGaC), it is not always performed as standard of care outside East Asia. The recommended minimal examined lymph node (ELN) count in nmGaC to stage cancer accurately varies largely across guidelines, and the optimal count to satisfactorily stratify patient survival has yet to be determined. This large cohort study aimed at robustly defining the minimal and optimal thresholds of examined lymph node (ELN) number in non-metastatic gastric adenocarcinoma (nmGaC).
Data on nmGaC patients operated in 2010-2016 and surviving ≥3 months were retrieved from the US SEER-18 Program and a Chinese multi-institutional gastric cancer database (MIGC). The correlation of ELN count with stage migration and patient survival were quantified with the use of the multivariable-adjusted logistic and proportional hazards Cox models, respectively. The sequences of odds ratios (ORs) and hazard ratios (HRs) for each additional ELN were smoothed, and the structural breakpoints were determined.
Together 7,228 patients from the US and 1,468 from China were analyzed, encompassing 23,114 person-years of follow-up. The mean ELN count was 20 in the US and 30 in China. With more ELNs, both cohorts significantly showed proportional increases from lower to higher nodal stage (OR = 1.03, 95%-CI = 1.03-1.04; OR = 1.02, 95%-CI = 1.02-1.03) and sequential enhancements in postoperative survival (HR = 0.97, 95%-CI = 0.97-0.97; HR = 0.98, 95%-CI = 0.97-0.99). Correlations for both stage migration and survival were still significant in most subgroups by patient, cancer, and management factors. Breakpoint analyses revealed a minimum threshold ELN count of 17 and an optimum count of 33, which were validated in both cohorts with good efficacy to differentiate probabilities of both stage migration and survival.
In resected nmGaC patients with anticipated survival ≥3 months, more ELNs are correlated with more accurate staging, which may partly explain the survival correlation. This observational investigation does not indicate causality. Our findings robustly conclude 17 ELNs as the minimum and propose 33 ELNs as the optimum thresholds, to assess the quality of lymph node examination and to stratify postsurgical survival.
虽然大多数指南提倡对非转移性胃腺癌（nmGaC）行D2淋巴结清扫术，但在东亚以外地区，这并不总是作为标准治疗方案实施。nmGaC中为准确分期而推荐的最小检查淋巴结（ELN）数量在不同指南中差异很大，而能令人满意地对患者生存进行分层的最佳数量尚未确定。这项大型队列研究旨在明确非转移性胃腺癌（nmGaC）中检查淋巴结（ELN）数量的最小和最佳阈值。
从美国SEER-18计划和一个中国多机构胃癌数据库（MIGC）中检索2010年至2016年接受手术且存活≥3个月的nmGaC患者的数据。分别使用多变量调整的逻辑回归模型和比例风险Cox模型量化ELN数量与分期迁移和患者生存的相关性。对每增加一个ELN的优势比（OR）和风险比（HR）序列进行平滑处理，并确定结构断点。
共分析了来自美国的7228例患者和来自中国的1468例患者，随访时间共计23114人年。美国患者的平均ELN数量为20个，中国患者为30个。ELN数量越多，两个队列均显著显示从较低到较高淋巴结分期呈比例增加（OR = 1.03，95%置信区间 = 1.03 - 1.04；OR = 1.02，95%置信区间 = 1.02 - 1.03）以及术后生存率持续提高（HR = 0.97，95%置信区间 = 0.97 - 0.97；HR = 0.98，95%置信区间 = 0.97 - 0.99）。按患者、癌症和管理因素划分的大多数亚组中，分期迁移和生存的相关性仍然显著。断点分析显示ELN数量的最小阈值为17个，最佳数量为33个，这在两个队列中均得到验证，对区分分期迁移和生存概率具有良好效果。
在预期生存≥3个月的接受手术的nmGaC患者中，更多的ELN与更准确的分期相关，这可能部分解释了生存相关性。这项观察性研究并未表明因果关系。我们的研究结果有力地得出结论，17个ELN为最小阈值，并建议33个ELN为最佳阈值，以评估淋巴结检查质量和对术后生存进行分层。
