Benign intratracheal thyroid: a possible cause for preoperative overstaging

We report a rare case of intratracheal thyroid ectopia in the setting of papillary thyroid carcinoma, resulting in the preoperative clinical impression of an aggressive, high-stage tumor. A 24-year-old opera singer presented with complaints of a gagging or choking sensation. The results of computed tomography revealed a mass in the left thyroid lobe with multiple small calcifications consistent with papillary thyroid carcinoma as well as a soft tissue mass in the adjacent left tracheal lumen thought to be direct invasion by the thyroid tumor. A total thyroidectomy was performed including excision of half of the first and second tracheal cartilages and the lower portion of the hemicricoid cartilage. The final histological findings revealed that the intratracheal component was composed of benign thyroid tissue and strands of benign thyrocytes coursed through the first tracheal membrane. Intratracheal thyroid ectopia is a rare symptomatic occurrence with a striking female predisposition. We have identified 23 cases of intratracheal thyroid ectopia from the literature. They occur most often at the level of the cricoid, usually posteriorly with a slight predisposition for the left side. Continuity between the intratracheal component and the thyroid lobe may be seen. Clinicians and pathologists must be aware of this entity to avoid mistaking it for evidence of thyroid invasion by a malignant neoplasm.