Abstract: Objective To construct and validate a multimodal imagebased prediction model for the efficacy of neoadjuvant chemotherapy in breast cancer.Methods  The 121 patients with breast cancer with ipsilateral axillary lymph node metastasis admitted to the hospital from January 2020 ~ April 2024 were reviewed.The patient underwent surgical resection after neoadjuvant chemotherapy and the pathological complete response (pCR) was counted.High-resolution MRI,breast ultrasound and mammography were performed before and after neoadjuvant chemotherapy.Logistic regression was used to analyze the influencing factors of the neoadjuvant chemotherapy effect in breast cancer patients,and a multimodal imaging based on multimodal imaging was constructed to predict the effect of neoadjuvant chemotherapy for breast cancer,and the model was verified and evaluated for efficacy.Results  Twenty-eight cases achieved pCR.Logistic regression analysis showed that tumor stage (OR=4.899,95%CI:2.016~11.909),△apparent diffusion coefficient (ADC) (OR=4.419,95%CI:1.818~10.741),and △ time to peak (TTP) (OR=3.644,95%CI:1.499~8.855) were the factors affecting the effect of neoadjuvant chemotherapy in breast cancer patients (P<0.05).The nomogram prediction model was established with the above influencing factors as predictors,and the risk rate ranged from 0.56~0.68.The results of nomogram model validation showed that the calibration curve for predicting the effect of neoadjuvant chemotherapy for breast cancer was close to the ideal curve (P>0.05).The ROC curve showed that the nomogram model had a sensitivity of 78.57%,a specificity of 83.87%,and an AUC of 0.851 (95%CI:0.767~0.927) in predicting the effect of neoadjuvant chemotherapy in breast cancer.Conclusion Tumor stage,△ADC and △TTP are closely related to the effect of neoadjuvant chemotherapy in breast cancer patients,and the prediction model of neoadjuvant chemotherapy effect based on multimodal imaging has good predictive performance.

Key words: breast cancer, multimodal image, neoadjuvant chemotherapy