Follicular Thyroid Carcinoma Presenting as Massive Skull Metastasis: A Rare Case Report and Literature Review

Follicular carcinoma of thyroid is a well differentiated thyroid malignancy. It is slow growing in nature and tends to metastasize to remote organs in advanced stage by hematogenous route. Lung and bone are the two most common sites of metastasis. In most of the reported cases of follicular thyroid carcinoma metastasizing to the skull, metastases occurred long after the diagnosis and institution of treatment for primary cancer. Very few cases have been reported with occult follicular thyroid carcinoma presenting as skull metastasis. A 48-year-old female patient presented with massive swelling in the frontal region of skull associated with swellings in occipital region. Evaluation confirmed that it is multiple metastases to skull bones from follicular thyroid carcinoma. This is a very rare presentation with such a large size of metastasis. We report this case of a metastatic follicular thyroid carcinoma presenting as massive skull tumor at our institution.