Utility of synthetic MRI in predicting pathological complete response of various breast cancer subtypes prior to neoadjuvant chemotherapy

AIM: To evaluate the usefulness of synthetic magnetic resonance imaging (MRI) performed before the initiation of neoadjuvant chemotherapy (NAC) in predicting whether breast cancers can achieve a pathological complete response (pCR) after the completion of NAC.MATERIALS AND METHODS: This retrospective study investigated 37 consecutive patients with 39 breast cancers (pCR: 14, and non-pCR: 25) who underwent dynamic contrast -enhanced (DCE)-MRI and synthetic MRI before the initiation of NAC. Using synthetic MRI images, quantitative values (T1 and T2 relaxation times, proton density [PD] and their standard deviations [SD]) were obtained in breast lesions, before (Pre-T1, Pre-T2, Pre-PD, SD of Pre-T1, SD of Pre-T2, SD of Pre-PD) and after (Gd-T1, Gd-T2, Gd-PD, SD of Gd-T1, SD of Gd-T2, SD of Gd-PD) contrast agent injection. The aforementioned quantitative values and several morphological features that were identified on DCE-MRI were compared between pCR and non-pCR.RESULTS: Multivariate analyses revealed that the SD of Pre-T2 (p1/40.038) was significant and was an independent predictor of pCR, with an area under the receiver operating characteristics curve of 0.829. The sensitivity, specificity, and accuracy of the SD of Pre-T2 with an optimal cut-off value of 11.5 were 71.4%, 80%, and 76.3%, respectively.CONCLUSIONS: The SD of Pre-T2 obtained from synthetic MRI was used successfully to predict those breast cancers that would achieve a pCR after the completion of NAC; however, these results are preliminary and need to be verified by further studies.(c) 2022 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.

Automated summary

Synthetic MRI was used to predict pathological complete response in breast cancers after neoadjuvant chemotherapy, with SD of Pre-T2 being a significant and independent predictor of pCR. The results suggest potential for clinical application pending further verification.