Quantitative ultrasound radiomics for monitoring radiation-induced toxicity following breast radiotherapy

Abstract

Radiotherapy (RT) is a standard treatment component for early-stage breast cancer. Despite the improved tumor control, RT-induced toxicity can negatively impact patient's quality of life. This study aims to develop a quantitative toxicity assessment technique using breast ultrasound (BUS) radiomics. We conducted a longitudinal imaging study with 30 patients receiving RT for breast cancer. Each patient received BUS scans at five time points from 1-2 weeks before RT to one year post RT. BUS scans were performed bilaterally to account for patient variations. Our radiomics analysis start with an automatic breast surface detection, and then a region of interest uses the skin surface as the upper bound and includes both cutaneous and subcutaneous breast tissues. Radiomics of both histogram and second-order textural features are extracted. In total, we extract 163 radiomic features from both irradiated and contralateral breasts and used their relative differences to characterize the breast toxicity, and p values are calculated with the pairwise t-test. To eliminate redundant features, we used the correlation coefficient and variance inflation factors (VIFs) to screen out collinearity. Overall, 23 out of 163 radiomic features were selected as significantly different (p < 0.05) between the irradiated and contralateral breast, with the greatest difference (57%) at 3 months post RT. This study has demonstrated that BUSbased radiomic features can be utilized to quantitatively evaluate and monitor radiation-induced toxicity.