Large skull metastasis: follicular thyroid primary

Case contributed by Frank Gaillard
Diagnosis certain

Note: This case has been tagged as "legacy" as it no longer meets image preparation and/or other case publication guidelines.

MRI scan shows a large complex solid and cystic mass that erodes the skull and shows an intracranial extension.

Case Discussion

Final Diagnosis: Scalp lesion, core needle biopsy: Thyroid tissue, highly suspicious for metastatic follicular thyroid carcinoma.

The biopsy shows well differentiated thyroid tissue, with no cytologic features of papillary thyroid carcinoma. Thyroid differentiation is confirmed by immunohistochemical stains that show expression of thyroglobulin and TTF-1.

This should be considered to be metastatic follicular thyroid carcinoma until proven otherwise. If this patient has no history of previous thyroid surgery, then investigations to identify the site of origin of the tumor are needed. Possible sites include the thyroid gland, sites of potential aberrant localization of thyroid tissue (such as mediastinum), as well as ovarian germ cell tumor.

How to use cases

You can use Radiopaedia cases in a variety of ways to help you learn and teach.

Creating your own cases is easy.