Association between multi-phasic MRI radiomic features and treatment response after stereotactic body radiation therapy

Abstract

Purpose: In this study, we analyse the association of radiomic features extracted from multi-phasic MRI scans and treatment response of patients who underwent stereotactic body radiation therapy (SBRT) and overall survival (OS). Methods and Materials: A prospective cohort of 24 patients diagnosed with hepatocellular carcinoma (HCC) who underwent SBRT was analysed. Each patient received multi-phasic MRI scans at pre-treatment and 3-months post-treatment using gadoxetic acid (gadoxetate) contrast agent. Several sequences were analysed including pre-contrast, dynamic phases, 10 minutes and 20 minutes post-contrast, and T2W for radiomic features (103 extracted features). Volumetric ADC values were also extracted for each lesion. Univariate logistic regression model was used to analyse the association between pre- and post-treatment radiomic features/ADC and treatment response (infield recurrence and overall survival). The performance of the features was assessed by ROC analysis using leave-one-out cross-validation. Results: Radiomic features from GLCM texture features were found to be most associated with treatment response. Features extracted from 10-minute delayed phase scans were found to be highly associated with infield recurrence (AUC = 0.7-0.85). For OS, GLCM features extracted from arterial phase scans and portal venous phase scans were found to the most associated (AUC = 0.65-0.76). No significant association was found with features extracted from pre-contrast, T2W and 20-minute delayed phases. No association was found between SBRT dose and changes in ADC values. Conclusion: We have found a strong association in radiomic features extracted from different MRI phases and infield recurrence in HCC patients treated with SBRT and overall survival. No association was found between ADC values and treatment parameters.