A Case of Minimally Invasive Follicular Thyroid Carcinoma Relapsed as a Large Cervical Lymphadenopathy and Multiple Lung Metastases

Minimally invasive follicular thyroid carcinoma (MIFTC) is a well-differentiated thyroid carcinoma showing subtle capsular invasion and/or 1 to 3 foci of vascular invasion only. Currently, no reliable methods exist that can identify MIFTC in the preoperative stage due of a lack of atypia in follicular cells in fine-needle aspiration cytology and high resemblance to goitre upon radiological examination. True to its name, a MIFTC shows excellent prognosis in the absence of systemic involvement. We report the case of an 81-year-old woman diagnosed with a MIFTC that relapsed as a large cervical lymphadenopathy and multiple lung metastases. This feature of MIFTC associated with rapid growing multiple metastases has not been previously reported.