Ectopic Papillary Thyroid Carcinoma Presenting as Right Lateral Neck Mass: A Case Report.

A lateral neck mass can be the initial presentation of a papillary thyroid carcinoma. A 24-year-old female presented with a 2.0 x 2.0 cm, non-erythematous, non-tender, right lateral neck mass. A neck ultrasound showed an enlarged right jugulodigastric (Level II) lymph node and a normal-sized thyroid gland exhibiting mild parenchymal disease with no nodules. Positron emission tomography-computed tomography scan (PET-CT) showed an enlarged intensely fluorodeoxyglucose (FDG)-avid right level III lymph node, which may be primary versus metastatic. Fine-needle aspiration biopsy (FNAB) of the lymph node showed the presence of atypical cells that are highly suspicious for metastatic carcinoma. A cervical lymph node excision biopsy was performed and histopathology showed metastatic papillary thyroid carcinoma. The patient underwent total thyroidectomy with neck dissection. The final histopathologic examination of the thyroid gland revealed chronic lymphocytic thyroiditis with the lymph nodes negative for metastasis. She eventually underwent radioactive iodine ablation (RAI) with a dose of 30mCi. Post-RAI whole-body scan showed functioning thyroid tissue remnants with no distant metastasis. This case adds to the limited data that ectopic thyroid carcinoma can be present in patients who initially present with neck masses.