Development of a clinical nomogram for prediction of response to neoadjuvant chemotherapy in patients with advanced gastric cancer

BACKGROUND The efficacy of neoadjuvant chemotherapy(NAC)in advanced gastric cancer(GC)is still a controversial issue.AIM To find factors associated with chemosensitivity to NAC treatment and to provide the optimal therapeutic strategies for GC patients receiving NAC.METHODS The clinical information was collected from 230 GC patients who received NAC treatment at the Central South University Xiangya School of Medicine Affiliated Haikou Hospital from January 2016 to December 2020.Least absolute shrinkage and selection operator logistic regression analysis was used to find the possible predictors.A nomogram model was employed to predict the response to NAC.RESULTS In total 230 patients were finally included in this study,including 154 males(67.0%)and 76 females(33.0%).The mean age was(59.37±10.60)years,ranging from 24 years to 80 years.According to the tumor regression grade standard,there were 95 cases in the obvious response group(grade 0 or grade 1)and 135 cases in the poor response group(grade 2 or grade 3).The obvious response rate was 41.3%.Least absolute shrinkage and selection operator analysis showed that four risk factors significantly related to the efficacy of NAC were tumor location(P<0.001),histological differentiation(P=0.001),clinical T stage(P=0.008),and carbohydrate antigen 724(P=0.008).The C-index for the prediction nomogram was 0.806.The calibration curve revealed that the predicted value exhibited good agreement with the actual value.Decision curve analysis showed that the nomogram had a good value in clinical application.CONCLUSION A nomogram combining tumor location,histological differentiation,clinical T stage,and carbohydrate antigen 724 showed satisfactory predictive power to the response of NAC and can be used by gastrointestinal surgeons to determine the optimal treatment strategies for advanced GC patients.