# Metastasis of oncocytic thyroid carcinoma in the mandibular condyle: An exceptional localization

## TL;DR

A rare case of thyroid cancer spreading to the jawbone is reported, emphasizing the need for aggressive treatment.

## Contribution

This is the first reported case of oncocytic thyroid carcinoma metastasis to the mandibular condyle.

## Key findings

- Oncocytic thyroid carcinoma can metastasize to the mandibular condyle, a rare location.
- Surgical removal of the affected condyle led to undetectable thyroglobulin levels post-surgery.
- Radical surgery and multidisciplinary care are crucial for managing such rare metastases.

## Abstract

Oncocytic thyroid carcinoma, previously known as Hürthle cell carcinoma, is a well-differentiated neoplasm accounting for 3-5% of malignant thyroid tumors. This type of carcinoma exhibits aggressive behavior with a propensity for lymphovascular invasion and distant metastases.

To present an unusual clinical case of oncocytic thyroid carcinoma metastasis to the right mandibular condyle, highlighting its surgical management and clinical significance.

An 86-year-old woman with a history of oncocytic thyroid carcinoma treated with total thyroidectomy and radioactive iodine in 2019. During follow-up, elevated thyroglobulin levels were detected, and a PET-CT scan revealed uptake in the right mandibular condyle. The lesion was confirmed by magnetic resonance imaging and surgical biopsy and was treated with a right condylectomy. Histopathological analysis revealed bone infiltration by oncocytic carcinoma. The patient had a favorable postoperative course, with undetectable serum thyroglobulin levels after surgery.

Bone metastases from oncocytic carcinoma are rare, with the lungs being the most common metastatic site. To our knowledge, this is the second reported case of mandibular metastasis and the first involving the mandibular condyle, underscoring the importance of radical surgical intervention and a multidisciplinary approach in such cases.

This case highlights the aggressive nature of oncocytic thyroid carcinoma and the importance of early diagnosis and personalized treatment to improve the prognosis of bone metastases.

Key words:Oncocytic thyroid carcinoma, bone metastases, mandible metastases.