ABSTRACT
Objective To evaluate the predictive value of serum carbohydrate antigen 50(CA50),tumor specific growth factor(TSGF),and tissue polypeptide antigen(TPA)levels for sensitivity to radiochemotherapy in patients with middle-and advanced-stage breast cancer using a nomogram model.Methods Eighty-two patients with middle-and advanced-stage breast cancer were selected as the study sub-jects.All patients received paclitaxel chemotherapy combined with radiotherapy and were divided into sensitive(n= 57)and insensitive(n= 25)groups according to the Response Evaluation Criteria in Solid Tumors.The general information of the patients,serum expression of CA50,TSGF,and TPA,and their differences before and after treatment were recorded.A nomogram model was constructed,and cali-bration curves,receiver operating characteristic(ROC)curves,and decision curves were used to evaluate the predictive power and clinical utility of the nomogram model.Results Significant differences were observed in tumor diameter,vascular invasion,TNM stage,lymph node metastasis,and degree of differentiation between the two groups(P＜0.05).Compared to those in the sensitive group,the serum expression of CA50,TSGF,and TPA after treatment was higher,and the difference in CA50,TSGF,and TPA was smaller in the insensitive group(P＜0.05).Three predictive variables were identified in the LASSO regression:differences in CA50,TSGF,and TPA.The logistic regression results showed that differences in CA50,TSGF,and TPA influenced sensitivity to radiochemotherapy in middle-and advanced-stage breast cancer(P＜0.05).A nomogram model was constructed using differences in CA50,TSGF,and TPA.Calibration,ROC,and decision curves showed the model's good predictive accuracy and clinical utility.Conclusion Serum expression of CA50,TSGF,and TPA is high in patients with middle-and advanced-stage breast cancer who are insensitive to radiochemotherapy,and differences in CA50,TSGF,and TPA affect their sensitivity to radiochemotherapy.The nomogram model had good predictive value and clinical utility.