Ependymomas with distant metastases.Report of 2 cases and review of the literature

Two new cases of intracranial ependymomas with extracranial metastases are reported. The metastatic sites are cervical lymph nodes and vertebra in one case and skull bones and femur in the other. The subject of metastasizing ependymomas is reviewed: 9 intracranial and 2 intraspinal ependymomas with remote metastases are found in the literature. No clear evidence of correlation can be established between (a) anaplasia of the primary tumor and the frequency of remote metastases, (b) cellular morphology and average survival time or (c) number of operations and frequency of metatases. Metastasizing intracranial ependymomas are 3 times as frequent in males and originate above the tentorium. The most effective transmission of metastatsis of ependymomas is through the blood stream; frequent sites for metastatic growth are as follows: lungs, pulmonary hilus, mediastinum, liver, scalp, vertebral and femoral bones, cervical lymph nodes.