Metastasis of renal carcinoma colliding with glioblastoma. Carcinoma to glioma: an event only rarely detected.

This report presents the case of a 74-year-old woman who was simultaneously affected by two highly malignant neoplasms, a metastasizing renal cell carcinoma and a glioblastoma with sarcomatous component. Leptomeningeal metastasis of renal carcinoma is shown to invade the glioblastoma at its margin. Especially in gliomas, "cancer to cancer" phenomenomal are only rarely documented. Support by immunohistochemical data may prove those events to be more frequent than assumed.