Post-treatment cell-free DNA as a predictive biomarker in molecular-targeted therapy of hepatocellular carcinoma.

BACKGROUND: Liquid biopsies, particularly those involving circulating tumor DNA (ctDNA), are rapidly emerging as a non-invasive alternative to tumor biopsies. However, clinical applications of ctDNA analysis in hepatocellular carcinoma (HCC) have not been fully elucidated. METHODS: We measured the amount of plasma-derived cell-free DNA (cfDNA) in HCC patients before (n = 100) and a few days after treatment (n = 87), including radiofrequency ablation, transarterial chemoembolization, and molecular-targeted agents (MTAs), and prospectively analyzed their associations with clinical parameters and prognosis. TERT promoter mutations in cfDNA were analyzed using droplet digital PCR. Furthermore, we performed a comprehensive mutational analysis of post-treatment cfDNA via targeted ultra-deep sequencing (22,000× coverage) in a panel of 275 cancer-related genes in selected patients. RESULTS: Plasma cfDNA levels increased significantly according to HCC clinical stage, and a high cfDNA level was independently associated with a poor prognosis. TERT promoter mutations were detected in 45% of all cases but were not associated with any clinical characteristics. cfDNA levels increased significantly a few days after treatment, and a greater increase in post-treatment cfDNA levels was associated with a greater therapeutic response to MTAs. The detection rate of TERT mutations increased to 57% using post-treatment cfDNA, suggesting that the ctDNA was enriched. Targeted ultra-deep sequencing using post-treatment cfDNA after administering lenvatinib successfully detected various gene mutations and obtained promising results in lenvatinib-responsive cases. CONCLUSIONS: Post-treatment cfDNA analysis may facilitate the construction of biomarkers for predicting MTA treatment effects.

Impact of direct-acting antivirals on early recurrence of HCV-related HCC: Comparison with interferon-based therapy.

BACKGROUND & AIMS: It remains controversial whether direct-acting antivirals (DAAs) accelerate the recurrence of hepatitis C-related hepatocellular carcinoma (HCC) after curative therapy. This study aimed to evaluate HCC recurrence after DAA treatment of chronic hepatitis C. METHODS: We enrolled patients with a history of successful radiofrequency ablation treatment for hepatitis C-related HCC who received antiviral therapy with DAAs (DAA group: 147 patients) or with interferon (IFN)-based therapy (IFN group: 156 patients). We assessed HCC recurrence rates from the initiation of antiviral therapy using the Kaplan-Meier method and evaluated risk factors for HCC recurrence by multivariate Cox proportional hazard regression analysis. The recurrence pattern was categorized as follows: intrahepatic recurrence with a single tumor <2 cm (stage 0), a single tumor or up to 3 tumors ≤3 cm (stage A), multinodular (stage B), and extrahepatic metastasis or macrovascular invasion (stage C). RESULTS: The recurrence rates at 1 and 2 years were 39% and 61% in the IFN group and 39% and 60% in the DAA group, respectively (p = 0.43). Multivariate analysis identified higher lens culinaris agglutinin-reactive fraction of alpha-fetoprotein level, a history of multiple HCC treatments, and a shorter interval between HCC treatment and initiation of antiviral therapy as independent risk factors for HCC recurrence. HCC recurrence in stage 0, A, B, and C was found in 56 (41%), 60 (44%), 19 (14%), and 1 (0.7%) patients in the IFN group and 35 (44%), 32 (40%), 11 (14%), and 2 (2.5%) patients in the DAA group, respectively (p = 0.70). CONCLUSIONS: HCC recurrence rates and patterns after initiation of antiviral therapy did not differ between patients who received IFN-based therapy and DAA therapy. LAY SUMMARY: We detected no significant difference in early hepatocellular carcinoma (HCC) recurrence rates and patterns between patients who received interferon-based and direct-acting antiviral therapy after HCC treatment. High lens culinaris agglutinin-reactive fraction of alpha-fetoprotein level, short recurrence-free period, and a history of multiple HCC treatments were independent risk factors for early HCC recurrence after the initiation of antiviral therapy.