Department of Surgery, Chang Gung Memorial Hospital, Linkou & Chang Gung University, Taiwan.
Department of Pathology, Chang Gung Memorial Hospital, Linkou & Chang Gung University, Taiwan.
Eur J Surg Oncol. 2022 Apr;48(4):783-788. doi: 10.1016/j.ejso.2021.11.117. Epub 2021 Nov 19.
Investigation of lymph node micrometastasis (mN) of gastric cancer has been focused on either T1 disease or T1-4N0 disease. Yet, it is unclear whether standard management algorithm toward poorly differentiated gastric cancer (PDGC) is more vulnerable to existence of mN, given its inherently biological aggressiveness, as compared with other histological types.
A surgical series (n = 3456) of gastric cancer categorized by histological differentiation was enrolled to analyze survival stratification. Of them, a cohort of T1-T4 N0 PDGC (n = 100) were subjected to cytokeratin immunohistochemistry, a surrogate of mN.
Cancer-specific survival by AJCC8 staging system could be nicely differentiated in both well-/moderately differentiated and signet ring cell types, while those between stage IA versus IB (p = 0.105), and stage IB versus IIA (p = 0.141) in PDGC could not. Thirteen (13%) out of 100 node-negative PDGC cases exhibited mN, with 5, 2, 5 and 1 cases occurring in T1, T2, T3, and T4 stage, respectively, without identifiable contributing factors. Prognostic performance of AJCC8 working upon PDGC became more discriminative by incorporating mN, as hazard ratio of stage IIIC referenced to stage IA increased from 43 to 78.
Defective discriminative survival of PDGC by standard staging algorithm prompted us to survey mN occurring in T1-T4N0 PDGC. The prognostic performance of AJCC8 working upon PDGC was enhanced by incorporating mN. As so, we recommend documentation of mN exclusively on node-negative PDGC that helps unveil stage migration phenomenon and switch to appropriate adjuvant therapy in need.
目前对胃癌淋巴结微转移（mN）的研究主要集中在 T1 期或 T1-4N0 期疾病。然而，与其他组织学类型相比，由于其固有的生物学侵袭性，低分化胃癌（PDGC）标准治疗方案是否更容易存在 mN 尚不清楚。
本研究纳入了按组织学分化分类的胃癌手术系列（n=3456），以分析生存分层。其中，100 例 T1-T4N0 PDGC 患者接受了细胞角蛋白免疫组化分析，作为 mN 的替代物。
AJCC8 分期系统的胃癌特异性生存率在高/中分化和印戒细胞类型之间可以很好地区分，而 PDGC 中 IA 期与 IB 期（p=0.105）和 IB 期与 IIA 期（p=0.141）之间则无法区分。100 例淋巴结阴性 PDGC 中有 13 例（13%）患者存在 mN，分别发生在 T1、T2、T3 和 T4 期，无明显的致病因素。将 mN 纳入 AJCC8 后，PDGC 的预后性能变得更具鉴别力，IIIC 期相对于 IA 期的危险比从 43 增加到 78。
标准分期算法对 PDGC 生存的区分能力不足，促使我们调查 T1-T4N0 PDGC 中发生的 mN。将 mN 纳入 AJCC8 后，可提高 PDGC 的预后性能。因此，我们建议对淋巴结阴性的 PDGC 专门记录 mN，以揭示分期迁移现象，并根据需要切换至适当的辅助治疗。
