Small-cell lung cancer metastasis to a meningioma: Case report and review of the literature.

Tumor-to-tumor metastasis is a rare event with meningioma as the recipient tumor accounting for 20% of the reported cases. The most common primary cancers showing this phenomenon are lung and breast cancer. Most lung cancers metastasizing to a meningioma are due to lung adenocarcinoma with the literature containing only 3 prior reports of small-cell lung cancer showing this pattern of spread.