A systematic overview of radiation therapy effects in brain tumours

Abstract

A systematic review of radiation therapy trials in several tumour types was performed by The Swedish Council of Technology Assessment in Health Care (SBU). The procedures for evaluation of the scientific literature are described separately (Acta Oncol 2003; 42: 357-365). This synthesis of the literature on radiation therapy for brain tumours is based on data from 9 randomized trials and 1 meta-analysis. Moreover, data from 2 prospective studies, 3 retrospective studies and 4 other articles were used. In total, 19 scientific articles are included, involving 4,266 patients. The results were compared with those of a similar overview from 1996 including 11,252 patients. The conclusions reached can be summarized as follows: The conclusion from SBU 129/2 that curative treatment is not available for patients with high-grade malignant glioma (grade III and IV) is still valid. The survival benefit from postoperative radiotherapy compared to supportive care only or chemotherapy is about 3-4 months, as demonstrated in earlier randomized studies. Quality of life is now currently estimated and considered to be of major importance when reporting the outcome of treatment for patients with brain tumours. There is no scientific evidence that radiotherapy using hyper- and hypofractionation leads to longer survival for patients with high-grade malignant glioma than conventional radiotherapy. There is large documentation, but only one randomized study. There is some documentation to support the view that patients with grade IV glioma and poor prognosis can be treated with hypofractionation and with an outcome similar to that after conventional fractionation. A shorter treatment time should be convenient for the patient. Documentation of the benefit of a radiotherapy boost with brachytherapy is limited and no conclusion can be drawn. There is no scientific evidence that radiotherapy prolongs life for patients with low-grade glioma. There are some data supporting that radiotherapy can be used to treat symptoms in patients with low-grade glioma. As no controlled studies have been reported, no firm conclusion can be drawn.