ANALYSIS OF NEOADJUVANT CHEMOTHERAPY TREATMENT RESPONSE IN BREAST DCE MRI PATIENTS BASED ON ESTROGEN RECEPTOR STATUS AND GABOR FILTER DERIVED ANISOTROPY INDEX

Abstract

Estrogen Receptor (ER) is a molecular biomarker that plays an important role in evaluating the Neoadjuvant Chemotherapy (NAC) treatment response of breast cancer patients. ER (-) breast cancer patients have better tumor response rates than ER (+) patients due to NAC and the result of ER status could change after NAC. However, there are limited studies on the analysis of NAC treatment response using ER status. Further, manual quantification of treatment response is challenging and inconsistent across raters. In this work, an attempt has been made to objectively quantify the radiological differences of Dynamic Contrast Enhanced (DCE) MR images in ER (-) and ER (+) patients due to NAC using Gabor filter derived Anisotropy Index (AI). The images (113 subjects at 4 visits of NAC treatment) used in this study are obtained from the publicly available I-SPY1 dataset. Gabor filter bank is designed with 5 scales and 7 orientations, and AI is calculated from each Gabor energy within the patient group. Results show that AI values can statistically (p < 0.05) differentiate the radiological differences in ER (-) and ER (+) patients due to NAC. The percentage difference in the mean AI values of Visit 1 Vs Visit 4, Visit 1 Vs Visit 3, and Visit 2 Vs Visit 4 is high in ER (-) compared to ER (+) patients. Thus, Gabor filter derived AI could be used as an objective measure in evaluating NAC treatment response in ER (-) and ER (+) patients.