A Radiogenomic Model using MRI and Gene Signature to Predict Complete Response in Breast Cancer.

PURPOSE: Pathological complete response (pCR) after neoadjuvant chemotherapy (NAC) is strongly associated with improved survival. Radiogenomic approaches integrating MRI. radiomics with gene signatures may enhance pretreatment prediction of therapeutic.

RESPONSE: This study aimed to develop a radiogenomic model for predicting pCR in breast cancer using MRI radiomics combined with an immune-related 23-gene signature (IRSN-23).

MATERIALS AND

METHODS

We retrospectively analyzed 112 women with histologically confirmed breast cancer (pCR, n = 21; non-pCR, n = 91) who underwent pre-NAC MRI and had IRSN-23 scores derived from tumor tissue. Patients were assigned to training (n = 100) and validation (n = 12) cohorts. From pre-NAC MRI, 100 radiomic features were extracted. A support vector classifier was trained to predict pCR using three models: radiomics alone, IRSN-23 alone, and the combined radiogenomic model. Receiver operating characteristic (ROC) analysis and areas under the curve (AUC) were calculated. Kaplan-Meier survival analyses assessed relapse-free survival (RFS) and overall survival (OS) based on model-predicted pCR.

RESULTS

In the training cohort, AUCs (95 % confidence interval [CI]) were 0.83 (0.73-0.92) for IRSN-23, 0.76 (0.63-0.89) for MRI radiomics, and 0.93 (0.86-1.00) for the combined model. In the validation cohort, corresponding AUCs were 0.78 (0.49-1.00), 0.59 (0.20-0.99), and 0.89 (0.69-1.00). The combined model significantly outperformed MRI (p = 0.007) and IRSN-23 (p = 0.031) in the training cohort. Differences in RFS and OS according to model-predicted pCR did not reach statistical significance, although patients predicted to achieve pCR showed a trend toward longer survival.

CONCLUSION

Integrating MRI radiomics with IRSN-23 improved pCR prediction compared with either modality alone and may support treatment planning, while the observed associations with survival outcomes should be interpreted as exploratory.