Thirty patients with histologically confirmed posterior fossa ependymomas operated on between January 1976 and December 1988 were reviewed. The median age was 44 years (range, 1-69 yr). There were 7 children (aged 5 yr or younger) and 23 adults (aged 16 yr or older). There were 18 female patients and 12 male patients. Headache, nausea and vomiting, and disequilibrium were the most frequent symptoms. The most common findings were ataxia and nystagmus. Gross total resection was performed in 8 patients (27%), subtotal resection in 21 patients (70%), and biopsy in only 1 patient (3%), Tumors were low grade in 73% and high grade in 27%. Twenty-seven patients underwent posterior fossa radiotherapy (median dose, 5400 cGy). Fourteen patients also underwent spinal irradiation (median dose, 3520 cGy). Age was the only significant prognostic factor identified (P Neurosurgery 28:659-665, 1991)