UKCCSG STUDY OF ACCELERATED RADIOTHERAPY FOR PEDIATRIC BRAIN-STEM GLIOMAS

Purpose: Between 1991 and 1994, the United Kingdom Childhood Cancer St udy Group (UKCCSG) conducted a multicenter study to assess the efficie ncy and tolerability of accelerated radiotherapy in children with a di agnosis of poor-prognosis brain stem glioma, Methods and Materials: Pa tients eligible for study were those aged 3-16 years with tumors arisi ng in the pens, medulla, or midbrain, not previously treated with radi otherapy or chemotherapy. Histologic confirmation was not mandatory, b ut computed tomography or magnetic resonance imaging and clinical find ings had to be typical, and patients were selected with short prediagn osis symptom history (< 3 months), cranial nerve palsies or long tract signs, and intrinsic diffuse lesions on scanning. The treatment dose was 48.6 Gy in 27 fractions, increased to 50.4 Gy in 28 fractions in J anuary 1992, delivered twice daily (except weekends) with an interfrac tion interval of at least 8 h. Between January 1991 and July 1993, 28 available patients were recruited: 15 boys and 13 girls with ages rang ing between 3 and 13 years (median 6). Results: After treatment, neuro logic improvement sustained for a period of at least 6 weeks without s teroids was reported in 13 children (46%). On central review of postra diotherapy imaging, 50% of children showed evidence of partial respons e, but none exhibited a complete response. A further six patients (22% ) had stable disease. The median survival time was 37 weeks (8.5 month s); 1-year survival was 32%, and 2-year survival 11%. The pattern of r elapse was local in all 26 patients who died of their disease; 1 patie nt had evidence of leptomeningeal seeding. Acute radiation morbidity w as minimal, with only three patients (11%) exhibiting mild toxicity. N o evidence of radiation-induced necrosis was found radiologically or h istologically at postmortem. Ability to withdraw steroids following ra diotherapy was the single most important prognostic variable in our st udy. Conclusion: The results of this study are comparable to previous outcomes of studies with conventional and hyperfractionated radiothera py in poor-prognosis brain stem glioma. The fractionation regimen was shown to be tolerable with an acceptable morbidity profile. However, f urther research is required to improve the poor prognosis of these unf ortunate children. (C) 1997 Elsevier Science Inc.