Comparison of contrast-enhanced mammography and breast magnetic resonance in the evaluation of response to neoadjuvant chemotherapy

Abstract Objective: Contrast-enhanced mammography (CEM) is a relatively inexpensive and convenient new imaging method obtained by administering enhanced iodinated contrast agent using the dual-energy technique to evaluate tumor neovascularity. CEM provides similar morphological and physiological information to breast magnetic resonance (MRI), the gold standard for detecting breast cancer. We aimed to compare CEM techniques, which have increased in popularity in recent years, with MRI, which has been the gold standard imaging technique to date, using the histopathological evaluation of patients with breast cancer who were operated after receiving neoadjuvant chemotherapy (NAC). Material and Method: CEM and breast MRI images of patients who were scheduled for surgery due to locally advanced breast cancer were taken before and after NAC. Responses to treatment and residual tumor sizes of patients operated after NAC were recorded. Results: CEM estimated the residual tumor size to within 1 cm accuracy in 84.7% of the patients. MRI estimated the residual tumor size to within 1 cm accuracy in 76.4% of the patients. When we used histopathological evaluation as a reference, the Lin’s correlation concordance was higher for CEM than MRI. The sensitivity, NPV and PPV were higher compared to MRI. The superiority of MRI over CEM was its higher specificity rate. Conclusion: Our findings showed that in patients receiving NAC, CEM was superior to MRI in identifying patients with pathological complete response and was at least as successful as MRI in patients with residual tumor.