Background
Lenvatinib has significant antitumor effect on Radioiodine-refractory differentiated thyroid cancer (RRDTC). In the phase III SELECT trial, Lenvatinib showed a significant improvement in progression free survival (PFS) in patients with RRDTC compared to placebo. However, almost all of the participants experienced adverse effects. In the present study, we retrospectively evaluate the efficacy and safety in patients with RRDTC in the real-world practice.
Patients and Methods
Chart records and images of 51 consecutive RRDTC patients treated with Lenvatinib from July 2016 to May 2019 in two tertiary medical centers in southern Taiwan were retrospectively reviewed. The primary objective was the progression-free survival (PFS) according to Response Evaluation Criteria In Solid Tumors v1.1 (RECIST 1.1). Disease control was defined as objective tumor response plus stable disease. The safety assessment was regularly performed.
Results
The median PFS was not reached during follow-up. Partial responses (PR) and stable disease (SD) were achieved in 12 (24%) and 31 (61%) patients, respectively. Disease control (PR+SD) of >6 months was achieved in 31 (61%) patients. Almost all participants experienced adverse events. The mean daily dose of Lenvatinib was 11.1 mg, and dose interruptions/withdrawal due to adverse events in 26 (51%) of patients. The most common adverse events (any grade) in lenvatinib-treated patients were fatigue/asthenia/malaise (67%), hypertension (60%), and proteinuria (58%).
Conclusion
These results confirmed that Lenvatinib is an effective treatment for patients with RRDTC, even at a dose far lower than the recommended. Adverse events are frequently occurred and should be identified and managed appropriately.