Prognostic value of ADC measurements in predicting overall survival in patients undergoing 90 Y radioembolization for colorectal cancer liver metastases

To assess the ability of diffusion-weighted imaging (DWI) in predicting the overall survival in patients who underwent Yttrium 90 radioembolization ( Y-RE) for colorectal liver metastases (CLM) with other well-established clinical and imaging parameters by comparing the pre- and post-treatment apparent diffusion coefficient (ADC) values of the lesions. A total of 81 metastatic lesions of 27 consecutive patients who underwent DWI before and after the Y-RE session were enrolled in the study. ADC values were calculated from the entire (ADC ) and peripheral (ADC ) tumor on pre- and post-treatment DWI, and any relative increase in ADC >0% accepted as a functional imaging response. The impact of functional imaging response in addition to other well-known parameters including Response Evaluation Criteria in Solid Tumors (RECIST), hepatic tumor burden, Eastern Cooperative Oncology Group performance status (ECOG-PS) and the presence of extrahepatic metastases in predicting overall survival (OS) was assessed using Kaplan-Meier curves and Cox-regression analyses. The median OS of the patients was 10 months (range, 6-20 months) while the median OS of the responders being significantly longer than the non-responders for ADC and ADC (median 11 vs 7 months, P = 0.003; median 12 vs. 7 months, P