Recently, in Italy, the reimbursement for the use of rhTSH in preparing patients for radiometabolic treatment of iodine-avid metastases from differentiated thyroid cancer has been made possible. Intramuscular administration of rhTSH increases the radioiodine uptake and thyroglobulin production by thyroid cells. In addition to the previous indications on the use of rhTSH (mainly: serum thyreoglobulin assay with or without 131I scintigraphy and ablation with 131I of remnants in low risk patients), the reimbursement is now allowed for the treatment with radioiodine of iodine-avid loco-regional and distant metastases, in subjects with inability to reach adequate TSH levels and/or severe clinical conditions which could be potentially worsened by other concurrent diseases (history of stroke or transient ischemic attack, severe cardiac disease, renal failure or major psychiatric disorders). The Italian Medicines Agency (AIFA) approved this use (and added this hormone in the special list of drugs regulated by the D.Lgs 648/96) on the basis of a series of scientific evidences, proposed by a "team of experts". In the present paper we illustrate the scientific background of the use of rhTSH (clinical usefulness, economic considerations, aspects related to a better quality of life) that allowed the modification of the reimbursement and how it was made possible in the Italian legislative context.