CONTRAST- ENHANCEMENT US AND MRI FOR ASSESSING THE RESPONSE OF BREAST CANCER TO NEOADJUVANT CHEMOTHERAPY

PURPOSE: To evaluate the response of breast cancers to neoadjuvant chemotherapy (NAC) with second-generation contrast-enhanced ultrasound (CEUS) and magnetic resonance (MR). MATERIALS AND METHODS: We studied 16 women aged 33-74 years (mean, 53 years; median, 38 years) with locally advanced breast carcinoma or large operable breast cancer (>2 cm; T2-T4, N0-N3, M0) that had been detected by mammography, conventional ultrasonography, and biopsy. CEUS (with SonoVue, 5 ml) and MR (with Gd-DTPA; 0.2 mM/kg) were performed under blinded conditions before, during, and after 6-8 cycles of NAC. Lesions were measured and time/signal intensity (T/SI) curves were calculated during both the examinations. The data obtained were analyzed in light of the results of surgical pathology. RESULTS: Six patients had complete responses manifested by the disappearance of enhancement at both CEUS and MR. Six others had partial responses (reduction of lesion enhancement >50%). In 5/6, T/SI curves obtained with CEUS and MR were both indicative of malignancy (flat curves at CEUS, type I curves at MR); the sixth had a discontinuous curve at CEUS and a type II curve at MR. Four patients had lesional enhancement reductions of <50%. In 3, concordant pictures emerged from the analysis of T/SI curves (discontinuous curves in CEUS, type II and III curves in MR); the fourth had a flat CEUS curve and a type I MR curve. Responses to NAC classified on the basis of MR and CEUS findings showed good correlation with the pathological response. CONCLUSIONS: T/SI curves recorded during CEUS correlate with those obtained during MR and may be a valid index of response to the therapy.