PROGNOSTIC FACTORS AND THERAPEUTIC OPTIONS OF RADIOTHERAPY IN PEDIATRIC BRAIN-STEM GLIOMAS

Background: A retrospective analysis was made to clarify the relations hip between prognosis, radiation dose and survival of brain stem gliom as. Methods: From 1983 to 1995, 22 children with brain stem tumors wer e treated by radiotherapy in the Veterans General Hospital-Taipei. Twe lve patients had pathology proof and the remainder were diagnosed by c omputerized tomography and/or magnetic resonance imaging. Seven patien ts had postoperative radiotherapy. Fifteen patients had radiotherapy a s primary management, five of whom had adjuvant chemotherapy. All pati ents received 4000-7060 cGy, either in conventional daily or hyperfrac tionated twice daily radiotherapy. Survival from date of diagnosis was calculated by the Kaplan-Meier method. Univariate analyses and multiv ariate analyses were calculated by the log rank test and the Cox propo rtional hazard model, respectively. Results: Most patients showed impr ovement following treatment. The overall 2-year survival rate was 55.5 % with a median survival of 27.1 months. Two-year survival for patient s with primary management of operation and radiotherapy (n = 7), radio therapy alone (n = 10) and radiotherapy with adjuvant chemotherapy (n = 5) were 66.7, 50 and 53.3%, respectively. In univariate analysis, th e study revealed that the growth pattern of tumors and the simultaneou s presence of cranial neuropathy and long tract sign were significant prognostic factors (P = 0.017 and 0.036). A trend of better outcome wi th radiation dose >6600 cGy and the hyperfractionation scheme was also noted in our study (P = 0.0573 and 0.0615). However, only the hyperfr actionation scheme showed significance in multivariate analyses (P = 0 .0355). Survival was not significantly affected by age, gender or meth od of diagnosis. Conclusion: Radiotherapy appears to be an effective t reatment modality of brain stem tumors. Patients with both cranial neu ropathy and long tract signs had a poorer outcome. Hyperfractionated r adiotherapy may give better local control and lead to better survival.