Papillary thyroid carcinoma presenting as a lateral neck cyst.

BACKGROUND Solitary lateral cervical cystic mass is an uncommon presentation of papillary thyroid carcinoma. OBJECTIVES To report our recent experience in the diagnosis and management of papillary thyroid carcinoma presenting as a lateral neck cyst. METHODS Patients who had papillary thyroid carcinoma and presented as a painless lateral neck cyst at the Department of Surgery, Al-Ain Hospital, from April 2005 to June 2009 were retrospectively studied. Their clinical presentation, diagnosis and management were reviewed. RESULTS Five patients were studied. No thyroid nodules were clinically palpable in all patients. Fine needle aspiration cytology from the cyst was positive for papillary thyroid carcinoma in three patients (60 percent). Two patients were diagnosed after excisional biopsy. Three patients had total thyroidectomy with modified radical neck dissection and postoperative radioactive iodine ablation. Two patients preferred to travel overseas for treatment. Thyroid histopathological examination has shown papillary thyroid carcinoma in all operated patients with multiple microscopic foci in two of them. This was associated with multiple bilateral cervical lymph node involvement. CONCLUSIONS Metastatic papillary thyroid carcinoma presenting as a neck cyst is a diagnostic challenge. Excisional biopsy is indicated if fine needle aspiration cytology was inconclusive so as to rule out malignancy.