Agenesis of the isthmus of the thyroid gland

The thyroid is an endocrine gland composed of two lobes connected by the isthmus tissue. Thyroid isthmus agenesisis a rare condition, and only a few cases have been reported in the literature. Here, we discuss the case of a 56-yearoldfemale patient in whom agenesis of the thyroid isthmus was discovered incidentally during surgery for a multinodulargoitre. When agenesis of the isthmus is found, associated thyroid lobe agenesis and the presence of ectopicthyroid tissue must be considered. In addition, associated autoimmune thyroid nodule, thyroiditis, primary thyroidcarcinoma, metastasis, and amyloidosis must be considered in the differential diagnosis. Preoperative awarenessof potential agenesis of the isthmus and its associated thyroid anomalies in patients with planned thyroid surgerywill significantly contribute to safety during surgical procedures and result in fewer surgery-related complications.

Tam Metin

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