RESUMO
INTRODUCTION: Follicular thyroid carcinoma is the second most frequent type of well differentiated thyroid tumours. It is usually confined to the thyroid gland, however it can metastasize in a later stage of the disease. Signs and symptoms associated with bone metastasis are rare as first clinical manifestations. CASE REPORT: An 84-year-old female complained with acute paraparesis. Magnetic resonance imaging revealed an extensive intraosseous infiltrating lesion compatible with a bone metastasis from an occult tumour. Biopsy samples were compatible with bone metastasis from a follicular thyroid carcinoma. The patient was submitted to total thyroidectomy followed by iodine ablative therapy. DISCUSSION: Follicular thyroid carcinoma presentation with symptoms related to bone metastasis is rare. Patients with bone lesions, such as pathological fractures or compressive symptoms should be studied since they may have clinically unapparent lesions from an unknown tumour. Patients with FTC should be submitted to total thyroidectomy. Bone lesions may be addressed to improve quality of life however this decision depends on disease extent. CONCLUSION: Acute paraparesis is a rare form of presentation of thyroid carcinoma. These neoplasms must be taken into account when investigating metastasis to the bone from unknown neoplasms.
