Change in arterial tumor perfusion is an early biomarker of lenvatinib efficacy in patients with unresectable hepatocellular carcinoma

BACKGROUND: Lenvatinib is one of the first-line tyrosine kinase inhibitors used for unresectable hepatocellular carcinoma (HCC). In the present study, we evaluated the potential of early changes in the time-intensity curve (TIC) of arterial phase on contrast-enhanced ultrasound (CEUS) as early imaging biomarkers of lenvatinib efficacy. AIM: To evaluate the potential of the early changes in the TIC of CEUS as early imaging biomarkers of lenvatinib efficacy in patients with unresectable HCC. METHODS: We analyzed 20 consecutive patients with unresectable HCC treated with lenvatinib from March to November 2018. Tumor response at 8 wk was assessed by computed tomography using the modified Response Evaluation Criteria in Solid Tumors (mRECIST). CEUS was performed at baseline before treatment (Day 0) and on day 7 (Day 7), and the images were analyzed in the arterial phase for 20 seconds after the contrast agent arrived at the target tumor. Three perfusion parameters were extracted from the TICs: the slope of wash-in (Slope), time to peak (TTP) intensity, and the total area under the curve (AUC) during wash-in. The rate of change in the TIC parameters between Day 0 and Day 7 was compared between treatment responders and non-responders based on mRECIST. RESULTS: The rate of change for all TIC parameters showed significant differences between the responders (n = 9) and non-responders (n = 11) (Slope, P = 0.025; TTP, P = 0.004; and AUC, P = 0.0003). The area under the receiver operating curve values for slope, TTP, and AUC for the prediction of responders were 0.805, 0.869, and 0.939, respectively. CONCLUSION: CEUS may be useful for the early prediction of tumor response to lenvatinib therapy in patients with unresectable HCC.