CHILDHOOD OPTIC CHIASM GLIOMAS - RADIOGRAPHIC RESPONSE FOLLOWING RADIOTHERAPY AND LONG-TERM CLINICAL OUTCOME

Purpose: In children with chiasmal gliomas, radiation therapy can arre st progressive visual and neurologic impairment. We examined the radio graphic response and clinical outcomes after irradiation. Methods and Materials: Forty-two children (median age at diagnosis, 6.6 years) wit h chiasmal gliomas were managed as follows: 11 asymptomatic patients w ith neurofibromatosis-1 (NF-1) were observed only; 2 patients, less th an 3 years old, underwent surgery and chemotherapy to delay irradiatio n; and 29 patients with progressive disease received radiation with or without prior surgery or chemotherapy. Time to radiographic response, long-term tumor control and late sequelae were reviewed for the 29 ir radiated patients. Results: The probability of at least 50% radiograph ic response at 24 months after irradiation was 18.1% and increased to 38.2% by 48 months and 45.9% by 60 months. By actuarial analysis, the median time for such radiographic response was 62 months. For the 29 i rradiated patients, the 10-year freedom from progression and overall s urvival rates were 100% and 89%, respectively (median follow-up for su rviving patients, 108 months). Stabilization or improvement in vision occurred in 81% of 26 evaluable irradiated patients. Conclusions: Nota ble radiographic response may be observed years after irradiation. Rad iation therapy provides excellent long-term tumor control and vision p reservation or improvement in the majority of patients with progressiv e chiasmal gliomas. (C) 1997 Elsevier Science Inc.