Prognostic factors and therapeutic options of radiotherapy in pediatric brain stem gliomas

BACKGROUND: A retrospective analysis was made to clarify the relationshipbetween prognosis, radiation dose and survival of brain stem gliomas.METHODS: From 1983 to 1995, 22 children with brain stem tumors were treatedby radiotherapy in the Veterans General Hospital-Taipei. Twelve patientshad pathology proof and the remainder were diagnosed by computerizedtomography and/or magnetic resonance imaging. Seven patients hadpostoperative radiotherapy. Fifteen patients had radiotherapy as primarymanagement, five of whom had adjuvant chemotherapy. All patients received4000-7060 cGy, either in conventional daily or hyperfractionated twicedaily radiotherapy. Survival from date of diagnosis was calculated by theKaplan-Meier method. Univariate analyses and multivariate analyses werecalculated by the log rank test and the Cox proportional hazard model,respectively. RESULTS: Most patients showed improvement followingtreatment. The overall 2-year survival rate was 55.5% with a mediansurvival of 27.1 months. Two-year survival for patients with primarymanagement of operation and radiotherapy (n = 7), radiotherapy alone (n =10) and radiotherapy with adjuvant chemotherapy (n = 5) were 66.7, 50 and53.3%, respectively. In univariate analysis, the study revealed that thegrowth pattern of tumors and the simultaneous presence of cranialneuropathy and long tract sign were significant prognostic factors (P =0.017 and 0.036). A trend of better outcome with radiation dose > 6600cGy and the hyperfractionation scheme was also noted in our study (P =0.0573 and 0.0615). However, only the hyperfractionation scheme was alsonoted in our study (P = 0.0573 and 0.0615). However, only thehyperfractionation scheme showed significance in multivariate analyses (P =0.0355). Survival was not significantly affected by age, gender or methodof diagnosis. CONCLUSION: Radiotherapy appears to be an effective treatmentmodality of brain stem tumors. Patients with both cranial neuropathy andlong tract signs had a poorer outcome. Hyperfractionated radiotherapy maygive better local control and lead to better survival.