Solitary skull metastasis from follicular thyroid carcinoma: a case report

Introduction: Follicular thyroid carcinoma (FTC) is the second most common
malignant form of thyroid cancers. FTC is more common in women with a peak
incidence in the fifth and sixth decades of life. Invasion into blood vessels may
lead to distant metastasis to bone, lung, liver or elsewhere.
FTC rarely manifests itself as a distant metastatic lesion, especially as solitary
metastasis.
Case report: Here we present a 65 years old woman with nodular goiter with
cytologic diagnosis of adenomatous goiter.
In follow up, she presented with a skull mass which had an osteolytic appearance
in parietal bone.
Biopsy from skull mass, showed metastasis from FTC. This diagnosis was
confirmed in histologic examination of the thyroidectomy specimen.
Conclusion: Thus, in approaching thyroid nodules, the limitations of fine needle
aspiration-cytology in differentiation of follicular lesions must be remembered.
Also in patients with nodular goiter and evidence of metastasis, possibility of
thyroid carcinomas as primary origin should be considered.