MRI findings of lumbosacral metastasis from occult follicular thyroid cancer: report of a case.

A 63-year-old female was admitted to our hospital with bowel and bladder incontinence. Magnetic resonance imaging (MRI) showed a 13 × 12 × 12 cm mass invading the posterior regions of the L4, L5, S1 and S2 vertebrae with broad paravertebral soft tissue invasion. A Tru-cut biopsy of the mass was performed. The histopathological examination revealed metastatic follicular carcinoma of the thyroid. Thyroid functional tests were within the normal limits. Thyroid sonography revealed a heterogeneous, ill-defined, 14 × 9 mm hypoechoic solid nodule in the right lobe of the thyroid gland. On thyroid scintigraphy, an area of focal hyperactivity was detected in the right lobe at the nodule localization. Total thyroidectomy was performed, and the primary tumor pathology was determined to be follicular thyroid cancer. To our knowledge, only a few cases of lumbosacral cord compression as the initial manifestation of follicular thyroid carcinoma have been reported in the literature. We aimed to discuss the MRI findings of tumors in this age group with lumbosacral localization.