Role of scintigraphy with tumor-seeking agents in the diagnosis and preoperative staging of malignant thyroid nodules

The commonly used procedure for the diagnosis of thyroid nodule malignancy is based on high resolution thyroid ultrasonography (US) combined with US-g uided fine needle aspiration cytology (FNAC). The other imaging procedures have a limited role in malignancy diagnosis. However, nuclear medicine proc edures, particularly scintigraphy with tumor-seeking agents such as 201-tha llium (201-Tl), 99mTc-methoxy-isobutyl-isonitrile (99mTc-MIBI) and 99mTc-te trofosmin may play an important role in the differential diagnosis between benign and malignant thyroid nodules in cases of non-diagnostic or inadequa te FNAC. This type of scintigraphy can also be used in the follow-up of pat ients with cytologically 'high'-risk thyroid nodules such as Hurtle cell ad enomas and follicular adenomas. Furthermore, scans with tumor-seeking agent s can be helpful in determining the preoperative staging of thyroid carcino ma patients with locally advanced disease, and in accurately evaluating. th e extent, and consequently, the surgical management of the disease. (C) 200 0 Editions scientifiques et medicales Elsevier SAS.