Claudin18.2在不同类型胃腺癌样本及转移阶段表达一致性分析OA

Objective To investigate Claudin18.2 expression and concordance across different gastric adenocar-cinoma specimen types and to analyze its associations with clinicopathological features.Methods Paired endoscopic biopsy,surgical resection,and metastatic lymph node specimens were retrospectively collected from 85 patients with gastric adenocarcinoma;distant metastatic specimens were also available from 29 patients.Claudin18.2 protein ex-pression was assessed by immunohistochemistry.Concordance across specimen types was evaluated using kappa statis-tics and intraclass correlation coefficients(ICCs),and associations with clinicopathological features were analyzed.Results Claudin18.2 positivity rates in biopsy,surgical resection,metastatic lymph node,and distant metastatic specimens were 41.2%(35/85),32.9%(28/85),31.8%(27/85),and 44.8%(13/29),respectively.Heterogeneous Claudin18.2 expression between biopsy and resection specimens was observed in 43.6%of cases.Kappa values were 0.775(95%CI:0.64-0.91,P＜0.001)between resection and biopsy specimens and 0.812(95%CI:0.68-0.95,P＜0.001)between resection and metastatic lymph node specimens.The single-measure ICC across biopsy,resection,and metastatic lymph node specimens was 0.763(95%CI:0.68-0.83).Among 29 patients with distant metastases,the kappa value was 0.649(95%CI:0.37-0.93,P=0.001)between resection and distant metastatic specimens and 0.450(95%CI:0.13-0.77,P=0.025)between biopsy and distant metastatic specimens.Claudin18.2 expression was significantly associated with tumor differentiation(P＜0.05)but not with age,sex,Lauren classification,tumor lo-cation,or TNM stage.Conclusion Claudin18.2 expression showed high concordance among biopsy,surgical resec-tion,and metastatic lymph node specimens but lower concordance between biopsy and distant metastatic specimens.