MRI as a complementary tool for the assessment of suspicious mammographic calcifications: Does it have a role?

Introduction: Mammography remains the standard imaging modality for the identification and characterization of breast calcifications. However, its low specificity results in high biopsy rates in cases of suspicious calcifications.

Objectives: To evaluate the diagnostic performance of MRI as an additional tool in the assessment of suspicious mammographic calcifications and to identify the enhancement patterns most related to malignancy.

Methods: An observational, prospective, cross-sectional, bi-centre study was conducted including consecutive patients with suspicious calcification groups on mammography (BI-RADS® 4 and 5). Anatomopathological results obtained from biopsies were considered the reference standard, and the patients were followed up for at least two years. MRI examinations were interpreted by two radiologists in consensus. The chi-square test was used to evaluate the correlation between MRI features and histological results. The overall diagnostic performance of MRI for malignancy was calculated.

Results: 162 female patients were included (mean age, 53 years; range 34-82 years), with 163 mammographic lesions, of which 77 (47.2%) were benign, 64 (39.3%) malignant, and 22 (13.5%) precursor lesions on histopathology. Malignant lesions demonstrated a significantly higher presence of enhancement (56/64; 87.5%) than benign lesions (17/77; 22.1%) (p < 0.001). Non-mass enhancement (NME) was the morphology most related to malignant lesions (38/56; 67.9%). The accuracy, sensitivity, specificity, positive predictive value, and negative predictive value of MRI for malignancy were 81.5%, 87.5%, 77.8%, 71.8%, and 90.5%, respectively.

Conclusion: MRI performed as an adjunct tool allows to increase imaging specificity for malignancy in suspicious calcifications, which may contribute to reduce the need for biopsy.