Childhood optic chiasm gliomas: radiographic response following radiotherapy and long-term clinical outcome.

PURPOSE

In children with chiasmal gliomas, radiation therapy can arrest progressive visual and neurologic impairment. We examined the radiographic response and clinical outcomes after irradiation.

METHODS AND MATERIALS

Forty-two children (median age at diagnosis, 6.6 years) with chiasmal gliomas were managed as follows: 11 asymptomatic patients with neurofibromatosis-1 (NF-1) were observed only; 2 patients, less than 3 years old, underwent surgery and chemotherapy to delay irradiation; 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 irradiated patients.

RESULTS

The probability of at least 50% radiographic 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 irradiated patients, the 10-year freedom from progression and overall survival rates were 100% and 89%, respectively (median follow-up for surviving patients, 108 months). Stabilization or improvement in vision occurred in 81% of 26 evaluable irradiated patients.

CONCLUSIONS

Notable radiographic response may be observed years after irradiation. Radiation therapy provides excellent long-term tumor control and vision preservation or improvement in the majority of patients with progressive chiasmal gliomas.