Diffusion-Weighted Magnetic Resonance Imaging of Patients with Breast Cancer Following Neoadjuvant Chemotherapy Provides Early Prediction of Pathological Response – A Prospective Study

Abstract

The purpose of this study was to evaluate the capacity of diffusion-weighted magnetic resonance imaging (DW-MRI) for early prediction of pathological response in breast cancer patients undergoing neoadjuvant chemotherapy (NCT). This prospective unicentric study evaluated 62 patients who underwent NCT. MRI was performed prior to the start of treatment (MR1), after the first NCT cycle (MR2), and upon completion of NCT (MR3). Pathological response was used as the gold-standard. Patients’ median age was 45.5 years and the median tumor size was 40 mm. Twenty-four (38.7%) tumors presented complete pathological response (pCR). The percent increase in apparent diffusion coefficient (ADC) value between MR1 and MR2 was higher in the pCR group (p < 0.001). When the minimum increase in ADC between MR1 and MR2 was set at 25%, sensitivity was 83%, specificity was 84%, positive predictive value was 77%, negative predictive value was 89%, and accuracy was 84% for an early prediction of pCR to NCT. Meanwhile, there were no significant changes in major tumor dimensions between MR1 and MR2. In conclusion, an increase in ADC after the first cycle of NCT correlates well with pCR after the chemotherapy in our cohort, precedes reduction in tumor size on conventional MRI, and may therefore be used as an early predictor of treatment response.

Pretreatment apparent diffusion coefficient does not predict therapy response to neoadjuvant chemotherapy in breast cancer

“…After checking of full texts, 19 articles with incomplete data regarding ADC values were excluded. Overall, 22 studies met the inclusion criteria [ [13] , [14] , [15] , [16] , [17] , [18] , [19] , [20] , [21] , [22] , [23] , [24] , [25] , [26] , [27] , [28] , [29] , [30] , [31] , [32] , [33] , [34] ] ( Fig. 1 ).…”

Role of MRI to Assess Response to Neoadjuvant Therapy for Breast Cancer

“…10). As expected, changes in ADC have been found to predict response, although investigators have not agreed upon the timing of the MRI, which varies from after the first cycle of chemotherapy, 25,80 after the second cycle, 25 during midtreatment, 81 and after completion of therapy 81,82 (Fig. 11).…”

Current Landscape of Breast Cancer Imaging and Potential Quantitative Imaging Markers of Response in ER-Positive Breast Cancers Treated with Neoadjuvant Therapy

“…In breast cancer, based on a meta-analysis of five studies with 402 patients, ADC was moderately correlated to cellularity, suggesting that other cellular features involving the ECM, nucleic areas, stroma, parenchyma, tissue density, and cell membrane integrity may play a role in restricting water mobility in the tumor microenvironment [112]. Nevertheless, the increase in ADC is strongly associated with pCR following NAC [113][114][115][116][117][118] and may precede changes in tumor size measured by DCE-MRI [84,119,120].…”