Improved survival in cases of intracranial ependymoma after radiation therapy. Late report and recommendations.

A publication from the University of Rochester Cancer Center in 1975 suggested an improvement in the survival time of patients with intracranial ependymomas in whom an aggressive postoperative radiation therapy approach had been adopted. The regimen was tailored to the aggressiveness and spread patterns of these tumors and therefore considered the patient's age, tumor histopathology and location, and status of the subarachnoid space and cerebrospinal fluid (CSF). The authors proposed using whole brain (WB) fields for all patients with low-grade supratentorial tumors, and WB with cervical cord field extensions for low-grade infratentorial tumors if either group had no CSF or subarachnoid evidence of spinal metastases. They also proposed using craniospinal irradiation for all patients with high-grade ependymomas (regardless of location) or with low-grade infratentorial tumors with positive CSF or subarachnoid findings of spinal metastases. Recommended doses were as follows: 4500 rads to the whole brain, 5500 rads to the primary tumor volume, and 3000 to 4000 rads to the spine, depending on its subarachnoid status. Children aged 3 years or under were to receive 80% of these doses and more protracted daily treatments. Analysis of the updated experience indicates that in 51 patients treated with this approach these criteria have yielded a beneficial and consistent increase in the survival time. A 69% 10-year survival rate has been observed (75% for low-grade and 67% for high-grade ependymomas). A multifactorial analysis of survival by prognostic factors and by grouping of prognostic factors, analysis of failures, autopsy findings, and quality of survival is presented and discussed.