A drug used with pembrolizumab to treat endometrial cancer that got worse after other systemic therapy and cannot be treated with surgery or radiation therapy. It is used in patients whose cancer does not have certain mutations (changes) in genes involved in DNA repair. Lenvatinib mesylate is also used with everolimus to treat advanced renal cell carcinoma (a type of kidney cancer) that was treated with antiangiogenesis therapy (a type of anticancer therapy). It is also used alone to treat hepatocellular carcinoma (a type of liver cancer) that cannot be removed by surgery and has not already been treated. Lenvatinib mesylate is also used to treat thyroid cancer in certain patients with progressive, recurrent, or metastatic disease that did not respond to treatment with radioactive iodine. It is also being studied in the treatment of other types of cancer. Lenvatinib mesylate blocks certain proteins, which may help keep cancer cells from growing and may kill them. It is a type of tyrosine kinase inhibitor. Also called Lenvima.