Quantitative dynamic contrast-enhanced MRI parameters effectively predict treatment efficacy of neoadjuvant...

To investigate the predictive value of quantitative DCE-MRI parameters for estimating the treatment efficacy of neoadjuvant chemotherapy (NACT) in breast carcinoma (BC).

A retrospective analysis was conducted on 178 pathologically confirmed cases of BC, diagnosed via puncture biopsy, at The Second Affiliated Hospital of Anhui Medical University between January 2019 and June 2023. All patients received preoperative NACT. Based on postoperative pathological inspection results, 53 patients with grade IV-V pathological responses were included in the major histological response (MHR) group, and the remaining 125 with grade I-III pathological responses were assigned to the non-major histological response (NMHR) group. The pre- and post-chemotherapy early-phase enhancement rate (E₁), peak enhancement rate (E_max), and time to peak (T_max) on DCE-MRI were compared between the two patient cohorts. Quantitative parameters such as volume transfer constant (K^trans), rate constant (K_ep) and extravascular extracellular volume fraction (V_e) were obtained, and the post-NACT maximum tumor diameter (D-max) reduction rate and tumor volume reduction rate (TVRR) were calculated. Furthermore, the predictive efficacy of pre- and post-NACT quantitative DCE-MRI parameters for treatment responses was evaluated using receiver operating characteristic (ROC) curves.

The MHR group showed statistically higher post-NACT D-max reduction rate and TVRR than the NMHR group. The two patient cohorts were similar in pre-chemotherapy K_ep, but the pre-chemotherapy K^trans and V_e were lower in MHR; the post-chemotherapy K^trans, K_ep and V_e were all statistically different between groups (P < 0.05). The MHR group presented markedly lower E₁ and E_max values and statistically longer T_max compared to the NMHR group after NACT (all P < 0.05). The pre-NACT quantitative DCE-MRI parameters demonstrated limited prediction performance, with V_e showing the highest efficacy (AUC = 0.612); in contrast, post-NACT quantitative DCE-MRI parameters exhibited improved predictive accuracy, with K^trans demonstrating the best predictive performance (AUC = 0.801).

The pre-NACT quantitative DCE-MRI parameters are not effective in predicting the therapeutic outcome of NACT. However, the post-NACT DCE-MRI parameters provide accurate and reliable predictions of pathological responses, with K^trans showing the highest predictive value and considerable clinical applicability.