Pentavalent Tc-99m DMSA accumulation in a medullary carcinoma of the thyroid

A 52-year-old man complained of right upper abdominal pain. Abdominal echography and computed tomography (CT) studies were negative. The laboratory data showed an elevated carcinoembryonic antigen level. Two months later, he noticed a mass in the right neck, and echography showed mass lesions in both thyroid lobes. The serum calcitonin level was elevated. Aspiration biopsy was performed twice, but it did not show tumor tissues. Tc-99m (V)-DMSA imaging showed increased uptake in both thyroid lobes on early and delayed static studies (Fig. 1). In view of these findings, a total thyroidectomy was performed. Tc-99m (V)-DMSA imaging was very helpful in deciding to perform surgery by showing possible medullary carcinoma of the thyroid in both lobes.