Metastases of central nervous system neoplasms. Case report.

Tumor-to-tumor metastasis is a rare occurrence. Fewer than 100 cases have been reported, many being metastases from carcinomas to benign intracranial neoplasms, most often meningiomas. A case is presented of carcinoma metastatic to a glioma. The patient, who presented for evaluation of bifrontal headache, was found on computerized tomography to have a partially calcified right frontal mass. Craniotomy revealed an oligodendroglioma containing foci of adenocarcinoma. Further work-up disclosed an infiltrative ductal adenocarcinoma of the breast. It has been suggested that tumors of the central nervous system may provide a fertile substrate or an immunological "haven" for metastases.