Abstract
Objective: Sorafenib and lenvatinib have been used for treating cases of unresectable differentiated thyroid gland cancer (DTC). However, their use is not common, because DTCs are slow growing tumors, even in the advanced stages. In this study, we investigated the outcomes of these treatments for DTC at our department.
Methods: Between 2015 and 2020, sorafenib therapy was started in 6 patients, and lenvatinib therapy in 24 patients with unresectable DTC. The objective response rate (ORR) and disease control rate (DCR) for each of the treatments were calculated in accordance with RECIST version 1.1. The overall survival (OS) and progression-free survival (PFS) were determined. Adverse events occurring during the treatments were investigated in accordance with CTCAE version 5.
Results: Although the tumor size decreased in 3 out of 6 patients after sorafenib therapy, the rate of reduction did not satisfy the criteria for PR or CR (ORR: 0%). The best response was rated as SD in 5 out of 6 patients, and as PD in the remaining one patient (DCR: 83%). On the other hand, the response of lenvatinib therapy appeared to be remarkable. The ORR in the patients treated with lenvatinib therapy was 63%, including one case of CR, and the DCR was 96%. Both the 2-year OS and PFS rates were 54.5%, and median PFS duration was 16.5 months. All of the patients who received sorafenib therapy experienced hand-foot syndrome, and two patients (33%) developed grade 3/4 serious adverse effects. Among the patients who received lenvatinib therapy, proteinuria and hypertension were the most common adverse effects. Fifteen patients (63%) developed serious grade 3/4 adverse effects, including cerebral infarction in one case that led to death.
Conclusion: Sorafenib and lenvatinib appear to be effective agents for the treatment of patients with unresectable DTC. Especially, lenvatinib appeared to exert remarkable effect, although careful management of adverse effects was required.
