A thyroid function screening should also be performed in all CVT patients with a family history of thyroid disease, a high dietary iodine intake, an intake of thyrotoxic drugs (e.g., lithium, interferon α, or amiodarone) [75,76], who are smokers, have experienced recent psychological stress, or have neoplasms (i.e., ectopic thyroid hormone production) [77]. The gene discussed is TG; the disease is neoplasm.