Coexistence of pyriform sinus fistula, ectopic lingual thyroid, and ectopic cervical thymus

Abstract Objective We report an extremely rare case of coexistence of pyriform sinus fistula, ectopic lingual thyroid, and ectopic cervical thymus. Case report A 16-year-old girl with ectopic lingual thyroid had suffered repetitive painful swelling in the left anterior neck. Barium swallow radiography and computed tomography revealed a fistula arising from the pyriform sinus running down to the anterior neck. She underwent transcervical fistulectomy with preservation of the recurrent laryngeal nerve. Histopathological examination of the surgical specimen showed coexisting thymic tissue. Conclusion This illustrative case exemplifies the different embryological origin of the thyroid from that of the third and fourth pharyngeal pouch derivatives.