An occult Follicular Thyroid Carcinoma revealed by an Isolated Caudaequina syndrome: a Rare Presentation

Abstract

Background: Follicular thyroid cancer (FTC) is a well-differentiated thyroid cancer that accounts for 15-20% of all Thyroid cancers. It is more likely to manifest as a distant metastasis than PTC as it tends to spread hematogenously with bones being the second most common site of metastasis after lungs.We report an unusual case of an occult FTC revealed by caudaequinasyndrome secondary to spinal metastasis as a first clinical manifestation of the disease.Results: An 81 year old female presented to neurosurgery clinic with paraplegia and sphincteric dysfunction.Dorso-lumbo-sacral CT and MR imagingshowed an ill-limited expansilelytic tissue processinvolving L4, L5 and S1 vertebrae,extendinginto spinal canal with an invasion of caudaequina nerves. Biopsy'sresults wereconsistent with spinal metastasis of FTC.The patient was referred to the ENT department where a total thyroidectomy was carried out, and the primary tumor pathology was consistent with FTC. Conclusion:Caudaequinasyndrome secondary to spinal metastasis is very uncommon as an initial finding of FTC without any previous symptoms of malignancy.Early diagnosis and prompt management of the primary carcinoma and the metastatic lesion may extend long-term survival and allow a favorable prognosis. Thyroidectomy with radioactive iodine ablation increases the 10-year survival in patients with metastatic disease.