基于CT定量参数和肿瘤标志物的局部进展期胃癌新辅助免疫化疗病理反应的列线图预测模型研究OA

Objective:To explore the value of a nomogram incorporating CT radiomics and tumor markers in predicting pathological response to immunochemotherapy in locally advanced gastric cancer.Methods:A total of 276 patients with lo-cally advanced gastric cancer treated at our hospital between January 2022 and June 2025 were enrolled.All patients under-went neoadjuvant immunochemotherapy followed by pathological response assessment.Clinical baseline data,CT imaging pa-rameters,and tumor marker levels were compared between patients who achieved a pathological response and those who did not.Multivariable analysis was performed to identify factors influencing pathological response to neoadjuvant immunochemo-therapy in locally advanced gastric cancer.These factors were then incorporated into a nomogram for individualized prediction of pathological response.Results:Among 276 patients undergoing neoadjuvant immunochemotherapy for locally advanced gastric cancer,50.36%achieved a pathological response,while 49.64%did not.Among pathological responders,the pro-portions of patients with Borrmann type I～II,T2 stage,and N0 stage were 47.48%,23.02%,and 21.58%,respectively,which were significantly higher than those among non-responders(all P<0.05).In pathological responders,the standard-ized thickness of the tumor area,standardized CT value of the tumor area,and levels of carbohydrate antigen 125,carcino-embryonic antigen(CEA),and carbohydrate antigen 199 were 4.45(2.93,6.10),0.65(0.38,0.92),42.50(23.34,68.12)U/L,32.40(14.20,58.40)ng/mL,and 62.34(28.34,98.45)U/L,respectively.These values were signifi-cantly lower than those in pathological non-responders(P<0.05).Logistic regression analysis showed that Borrmann classi-fication,T stage,standardized thickness of the tumor area,and CEA level were independent factors significantly associated with pathological response(P<0.01).The nomogram achieved an AUC of 0.890(95%CI:0.853～0.928,P<0.05)for predicting pathological response,with a sensitivity of 85.6%and a specificity of 79.6%.Decision curve analysis demonstrated that the nomogram provided a positive net benefit across a threshold probability range of 0.1～0.94,indicating good clinical usefulness.Conclusion:The nomogram incorporating CT quantitative parameters and tumor markers serves as a valuable tool for predicting pathological response to neoadjuvant immunochemotherapy in patients with locally advanced gastric cancer.