Hickam's dictum: Angiosarcoma-to-meningioma metastasis.

Tumor-to-tumor metastasis is a seldom reported phenomenon whereby a neoplasm seeds within another histologically distinct tumor, with only 84 cases documented in the literature. We hereby describe the case of a 95-year-old woman who died of widespread metastases identified as a primary hepatic angiosarcoma on autopsy, and the interesting finding of a seeding foci within a dural meningioma. Although meningiomas are the most common intracranial neoplasms to harbor such a phenomenon, this is to our knowledge the first case where an angiosarcoma was identified as the donor tumor.