Favorable radiological antitumor response at 2 weeks after starting lenvatinib for patients with advanced hepatocellular carcinoma

Aim We aimed to investigate the radiological antitumor response at 2 weeks after starting lenvatinib for patients with advanced hepatocellular carcinoma in real-world practice. Methods This retrospective study enrolled 40 patients who received lenvatinib. Radiological antitumor response was evaluated according to the modified Response Evaluation Criteria in Solid Tumors. Results The objective response rate at 2 weeks and best overall response on confirmation of complete response, partial response (PR), and stable disease required (confirmed response) were 57.5% and 32.5%, respectively. Based on confirmed response, the overall survival rate was significantly longer in patients with an objective response rate than in those with stable disease or progressive disease after 12 months (73.2% and 54.2%, P = 0.0358). All 13 patients with an objective response rate on confirmed response were evaluated as PR at 2 weeks. The alpha-fetoprotein ratio at 2 weeks was a significant factor associated with PR of response rate at 2 weeks. The median relative dose intensity from 2 to 6 weeks was significantly lower than that from 0 to 2 weeks (69.6% vs. 100%, P < 0.0001). Stratified by the antitumor response at 6 weeks considering the image evaluation at 2 weeks, the median relative dose intensity from 2 to 6 weeks was significantly lower in patients with progressive disease than in those with PR or stable disease (45.2% vs. 72.6%, P = 0.0482). Conclusions The radiological antitumor response at 2 weeks was favorable. Information on a favorable visible therapeutic response very early after lenvatinib initiation can help patients maintain their motivation for treatment, and allow physicians to continue treatment effectively and safely.