Dagnostic challenge of thyroid-derived papillary carcinoma along the embryologic thyroid descent pathway: a report of three cases
Year: 2026
Type: article
Study design: Case Report
Abstract: Background: Thyroid tissue descends from the foramen cecum to the pretracheal neck. Remnants along this pathway may form ectopic thyroid tissue or thyroglossal duct cysts (TGDCs), and rarely develop papillary thyroid carcinoma (PTC). These tumors may mimic benign cystic or cystic-solid lesions, making risk stratification, diagnosis of origin, and surgical planning difficult. Case Description: Three women had thyroid-derived PTC at descent-pathway sites. Case 1 was a 33-year-old woman treated by Sistrunk procedure for presumed TGDC after fine-needle aspiration yielded cystic contents. Final pathology showed TGDC-PTC invading fibrous and skeletal muscle tissue, with BRAF V600E positivity; postoperative tongue-base and pharyngeal edema required emergency tracheotomy. Case 2 was a 29-year-old woman with a tongue-base lesion present before total thyroidectomy and central neck dissection for orthotopic pT1aN0M0 PTC. Transoral excision showed a 17-mm thyroid-derived PTC clinically favored as lingual thyroid PTC, with negative margins and no BRAF V600E or TERT promoter mutation; no local recurrence was seen at 15 months. Case 3 was a 57-year-old woman with an anterior midline hyoid-region lesion in which imaging suggested ectopic thyroid carcinoma or metastatic PTC. Frozen section confirmed thyroid-derived PTC with negative margins, supporting Sistrunk-type local excision and staged surveillance of the orthotopic thyroid; early postoperative ultrasound showed no suspicious cervical lymph node. Conclusions: Tongue-base, hyoid-region, and anterior midline lesions should be assessed together with the orthotopic thyroid and cervical lymph nodes. Histology and immunohistochemistry confirm thyroid follicular-cell origin but may not fully distinguish ectopic thyroid carcinoma, TGDC carcinoma, and metastatic PTC. Management should be guided by tumor size, invasion, margin and nodal status, orthotopic thyroid findings, molecular features, airway risk, and follow-up reliability.
Source: Gland Surgery
Institutions: Sichuan University, West China Hospital of Sichuan University
Language: English
Topic: Head and Neck Anomalies
Subfield: Surgery
Field: Medicine
Domain: Health Sciences
Open Access status: diamond
OpenAlex ID: W7223882282