RESUMO
Current treatment guidelines for follicular thyroid carcinoma (FTC) recommend total thyroidectomy, lymphadenectomy and radioiodine ablation. Considering the low malignant potential of minimally invasive follicular thyroid carcinoma (MIFTC), a limited radical therapeutic procedure may be adequate. MIFTC is an intensely discussed group of tumors and a review of the literature reveals disagreement among experts concerning the criteria for a distinct definition. Therefore, in 2005 Rosai proposed a clinically more significant classification of FTC based on the extent of capsular and vascular invasion: MIFTC with capsular invasion only, with limited (< or =3) vascular invasion, encapsulated FTC with extensive (>3) vascular invasion and broadly invasive FTC with extensive invasive growth.For the diagnosis of MIFTC a complete investigation of the encapsulated follicular lesion should be performed by the pathologist and examination of at least 10 tissue blocks is mandatory. Due to the excellent prognosis hemithyroidectomy constitutes an adequate therapeutic approach in MIFTC with capsular invasion only and may also be considered for MIFTC with limited vascular invasion. There are no indications for systematic lymphadenectomy.