Micro–Medullary Thyroid Carcinoma: A Diagnosis not to be Missed in a Patient With Neck Cavernous Hemangioma

ABSTRACT Objective: To present a rare case of co-existence of micro–medullary thyroid carcinoma (MTC) and neck cavernous hemangioma. Methods: We present the clinical, laboratory, imaging, and pathologic findings, along with review of the literature. Results: A 66-year-old woman was referred to our department due to osteopenia. Physical examination disclosed a mass at the right neck. Neck ultrasound (US) showed a 2-cm neck mass laterally to the right thyroid lobe and a hypoechogenic nodule 0.5 cm in the left thyroid with a taller than wide shape. A fine-needle aspiration (FNA) biopsy under US from the right side disclosed findings consistent with hematoma. Neck US follow-up disclosed increased dimensions of both lesions and FNA was repeated, including the left thyroid nodule. Cytology revealed same elements in the right side, while the left thyroid nodule disclosed cytology suspected for MTC. Laboratory tests pre-operatively disclosed high calcitonin. Total thyroidectomy with central neck dissection and resection of the right neck tumor was performed. The pathologic examination confirmed the diagnosis of micro-MTC on the left thyroid lobe and a cavernous hemangioma on the right neck with no lymph node metastasis. Postoperatively, calcitonin was undetectable. Conclusion: This case report represents for the first time the co-existence of cervical cavernous hemangioma with micro-MTC in the same patient. MTCs should be considered in nodules less than 10 mm with suspected US findings, and serum calcitonin measurement is recommended in such cases. Early pre-operative diagnosis of micro-MTC leads to favorable outcome. Abbreviations: FNA = fine-needle aspiration;MEN = multiple endocrine neoplasia;MTC = medullary thyroid carcinoma;US = ultrasound