Lenvatinib in Locally Advanced Invasive Thyroid Cancer

Inclusion Criteria: * 18 years of age at the time of informed consent and willing and able to provide written informed consent for the trial. * Adult participants who are either initially diagnosed with locally advanced thyroid neoplasm or have experienced persistent or recurrent thyroid and/or cervical nodal recurrent DTC (participants with M1 disease are allowed, AJCC 8th edition stage I-IVb)), including: * a. Papillary thyroid carcinoma (PTC) - classical and variants * Follicular variant * Variants including but not limited to tall cell, columnar cell, cribriform-morular, solid, oxyphil, Warthin's-like, trabecular, tumor with nodular fasciitis-like stroma, Hürthle cell variant of papillary carcinoma * b. Follicular thyroid carcinoma (FTC) * c. Hürthle cell carcinoma * d. Poorly differentiated thyroid carcinoma * e. Cytologically confirmed thyroid neoplasm, Bethesda 3, 4 and 5 * Evidence of extrathyroidal extension and/or locally invasive disease and deemed at risk for R2 resection by treating team on clinical and/or fiberoptic examination and/or radiographic evaluation in the primary or recurrent setting. Evidence of "at risk for R2 resection" includes: * a. Vocal cord paralysis by fiberoptic examination * b. Extrathyroid and/or extranodal extension on CT or MRI, including tracheal and/or laryngeal cartilage invasion, esophageal involvement, and/or involvement of perithyroid muscles (e.g. strap, sternocleidomastoid, inferior constrictor muscles) o…