Follicular carcinoma on a radio-treated ectopic lingual thyroid

A 61yrs woman came to our attention for a follicular extra-capsular carcinoma arising from an ectopic lingual thyroid. This patient underwent radiotherapy at 17 years of age for a lesion that was not recognized as an ectopic thyroid. Once diagnosis and staging were done (cT4a, N0, M0) the patient underwent a multiple surgical approach (endoscopic laser and open surgery) followed by metabolic radiotherapy. After 6 months,suspected laterocervical adenopathies were found and then confirmed as metastatic after bilateral functional neck dissection; five years after surgery no signs of pathological recurrence were found. Correlation between cancerization of ectopic thyroid and radiotherapy, the importance of an accurate differential diagnosis before choosing the correct treatment for a lesion of the base of the tongue, limits of intraoperative histological examination and guidelines of surgical treatment related to the site and the histological type of the tumour are discussed.