ABSTRACT:
Background: The presence of ectopic thyroid tissue is a developmental disorder that affects about one per 100 000–300 000 people. It is extraordinarily rare for ectopic thyroid to be out of the lines of its descent. This is the first case in the litterateur to report a cancerous ectopic thyroid in the mandibular bone with a goitrous orthotopic thyroid gland.
Case presentation: 80 years old female of free medical background presented to our clinic with painless left mandibular swelling that recently increased size after tooth extraction. Surprisingly the diagnosis of ectopic thyroid tissue with follicular carcinoma is reached upon histological analysis. The thyroid gland was found in its expected cervical location, and the patient was euthyroid.
Conclusion: Ectopic thyroid tissue should be included in the differential diagnoses of a mandibular mass. About 70% of ectopic tissues are non-functional.