Abstract
Lenvatinib is one the most active drugs in radioiodine-refractory differentiated thyroid cancer (RR-DTC) such that it has become an important therapeutic tool in tumor control and survival. Renal and hepatic impairments are common comorbidities in cancer patients. Treating these patients is a challenge that requires careful consideration. As a first approach to patients with RR-DTC and renal or hepatic impairment, Summary of Product Characteristics recommendations for lenvatinib use and dose adjustments should be strictly followed. Close clinical and blood monitoring is the gold standard approach to optimizing lenvatinib's use during the whole course of treatment.