Metastatic Gallbladder Carcinoma in Meningioma: A Case Report.

Metastases from tumors to systemic cancers are rare. The most common intracranial recipient tumor is meningioma. Metastasis from gallbladder cancer has been previously reported from only one patient during autopsy. We present the case of a 72-year-old woman who underwent surgery for right frontal skull base meningioma.The tumor was completely removed. Histological specimens showed gallbladder carcinomatous metastasis with diffuse neuroendocrine differentiation in meningothelial meningioma. The Ki-67 proliferation index of the meningioma was 3%. Further, 60% positive immunoreactivity with the progesterone receptor was observed in meningioma cells. In carcinoma cells, diffuse positive immunoreactivity with chromogranin, CDX2, CEA, panCK, cytokeratin 7, and synaptophysin was observed. A combination of molecular, metabolic, immunological, and/or hormonal factors may contribute to the pathogenesis of this lesion. It cannot be ruled out that it is more common than expected.