Calvarial metastasis from malignant pheochromocytoma associated with multiple endocrine neoplasia

BACKGROUND: Malignant pheochromocytoma is a rare neuroendocrine tumor that may metastasize to the bones, liver, lungs, kidneys, and lymph nodes. Cerebral and skull metastases are even rarer, with only 17 cases reported in the literature. To the best of the authors’ knowledge, this is the first reported case of a purely calvarial metastasis from malignant pheochromocytoma associated with multiple endocrine neoplasia type 2A (MEN2A). CASE DESCRIPTION: A 31-year-old Filipino man diagnosed with MEN2A was found to have elevated urine metanephrine on routine surveillance, and workup revealed right adrenal and hepatic masses and a focus of intense tracer accumulation on the right frontal bone on metaiodobenzylguanidine I-123 scan. All the newly discovered lesions were resected to achieve tumor control. Histopathology revealed a diagnosis of pheochromocytoma for the calvarial lesion. CONCLUSION: Malignant pheochromocytoma may give rise to indolent metastatic foci that can easily be missed without a thorough examination. Misdiagnosis and delays in management of this disease can be detrimental, resulting in irreversible complications and death.