Surgical resection of thyroid adenoma extending from the neck to the cranial mediastinum in a cat.

Thyroid adenomas in cats are typically functional, relatively small, and rarely exceed 1 cm in diameter. However, cystic and enlarged adenomas have been reported in rare cases. In this report, we describe a case of a non-functional thyroid adenoma extending from the cervical region to the cranial mediastinum that was successfully removed surgically, with a favorable postoperative outcome.