A Thyrotropin-Alfa stimulated total body scan with Iodine-123 is a nuclear medicine procedure used in patients with a history of thyroid cancer. Usually, patients have had their thyroid gland removed and are undergoing a routine check up to make sure the cancer has not returned. Thyrogen is like the body’s naturally produced hormone TSH ( Thyroid stimulating hormone). It is used to stimulate any thyroid cells that may exist in the body so they can absorb iodine and be visualized on the 123-Iodine nuclear medicine scan.