Ultrasonographic and cytologic findings of metastatic cancer in the thyroid gland

Background and purpose: Cancer metastasizing to the thyroid is not uncommon . Prompt diagnosis and aggressive treatment appear to contribute to better prognosis in some patients. The aim of this study was to determine the clin ical manifestations, ultrasonographic and cytologic findings, and outcomes in patients with metastatic thyroid cancer. Methods: We retrospectively reviewed the medical records, including clinica l courses, ultrasonographic and cytologic findings, and outcomes, of 14 pat ients with metastatic thyroid cancer. Results: There were various primary sites of cancer in our study population , with adenocarcinoma the most common. The sonographic images in five of 12 patients who underwent sonography showed diffusely heterogeneous hypoechoi c abnormalities, while the remaining seven patients had nodular lesions. Th e cytologic appearances of metastatic lesions in the thyroid were character istic of the primary malignancies. Conclusions: Most cancer metastatic to the thyroid presented as advanced me tastases of primary malignancies. The sonographic appearance alone was not the ideal discriminator, and fine needle aspiration cytology helped define the diagnosis and management strategy.