Papillary thyroid carcinoma in a branchial cleft cyst

Area of Science:

• Oncology
• Head and Neck Surgery
• Endocrinology

Background:

• Branchial cleft cysts (BCCs) are typically benign congenital anomalies.
• Papillary thyroid carcinoma (PTC) within a BCC is an exceedingly rare occurrence.
• Metastatic PTC can mimic BCC radiographically and histologically.

Purpose of the Study:

• To report a rare case of papillary thyroid carcinoma within a branchial cleft cyst.
• To discuss the diagnostic challenges and management of this rare presentation.
• To emphasize the importance of considering primary thyroid malignancy in BCCs.

Main Methods:

• Case report of a 53-year-old male with a BCC containing PTC.
• Preoperative imaging, including thyroid ultrasound.
• Total thyroidectomy with histopathological examination.
• Radioiodine ablation for treatment.

Main Results:

• The BCC contained multifocal bilateral micropapillary thyroid carcinoma.
• A contralateral metastatic lymph node was identified, indicating aggressive disease.
• Thyroid imaging was normal preoperatively.
• This represents the 11th reported case of PTC in a BCC.

Conclusions:

• Thyroid carcinoma can metastasize to a BCC.
• The possibility of primary PTC from ectopic thyroid tissue within a BCC exists.
• Total thyroidectomy is recommended even with normal thyroid imaging to exclude primary micropapillary thyroid tumors.
• Thyroglobulin assay may aid in preoperative diagnosis.