Validation of LI-RADS Treatment Response Algorithm after Loco-Regional Therapy of Hepatocellular Carcinoma

Background Hepatocellular carcinoma (HCC) is the third cause of cancer related death worldwide and liver cirrhosis is the most common predisposing factor for HCC. Loco-regional therapy as radiofrequency ablation (RFA) or trans-arterial chemoembolization (TACE) have very important role as potentially curative or palliative methods for treatment of HCC. Objective To investigate the potential application of LI-RADS Treatment Response [LRTR] algorithm in terminology and diagnostic performance after local- regional treatment of hepatic lesions. Methods During the period from September 2021 to March 2022, the present study included 31 patients: 26 were males and 5 were females with hepatocellular carcinoma treated by loco-regional therapy including 21 conventional TACE and 10 RF. Their ages ranged between 51 - 80 years with mean age of 70 years old. Results There were excellent inter-observer agreements between both reader radiologists regarding the classification of treated HCC: LR-TR viable, LR-TR non- viable and LR-TR equivocal according to major features of LIRADS. DWI and ADC as well as T1 and T2 pre-contrast signal are considered good ancillary features in evaluating post treatment response of treated HCC. Conclusion Our study demonstrates that LIRADS treatment response algorithm is a good reporting system for explaining the outcome of the treated HCC with loco-regional therapy as it doesn’t depend only on APHE and mentions that there is expected post-treatment enhancement pattern that does not denote viability. This isn’t found in modified RECIST criteria.