Development and external validation of a combined clinical-mammographic-MRI model for differentiating benign and malignant NME breast lesions

Motivation: Differential diagnosis of nonmass enhancement (NME) breast lesions is difficult. Goal(s): A combined clinical-mammographic-MRI based on DWI model can distinguish benign and malignant NME lesions. Approach: We retrospectively enrolled consecutive female patients with NME breast lesions who underwent pretreatment MG and breast MRI as the development cohort and prospectively collected eligible candidates as an internal validation group and an external validation group at our centre. A combined discriminatory model was developed through multivariable logistic regression and was validated internally and externally. Results: The combined model incorporating mammography, MRI, and clinical variables showed good discriminability in the development, internal validation, and external validation cohorts. Impact: Based on SHAP analysis, suspicious calcification on mammography and internal NME patterns were significant contributors to the performance of the model, and radiologists and clinicians should improve their awareness of complementary mammography to improve diagnostic performance in classifying NME lesions.