Purpose. Glioblastoma multiforme (GBM) is optimally treated by maximal debulking followed by combined chemoradiation. Intensity modulated radiation therapy (IMRT) is gaining widespread acceptance in other tumour sites, although evidence to support its use over three-dimensional conformal radiation therapy (3DCRT) in the treatment of gliomas is currently lacking. We examined the survival outcomes for patients with GBM treated with IMRT and Temozolomide. Methods and Materials. In all, 31 patients with GBM were treated with IMRT and 23 of these received chemoradiation with Temozolomide. We correlated survival outcomes with patient functional status, extent of surgery, radiation dose, and use of chemotherapy. Results. Median survival for all patients was 11.3 months, with a median survival of 7.2 months for patients receiving 40.05 Gray (Gy) and a median survival of 17.4 months for patients receiving 60？Gy. Conclusions. We report one of the few series of IMRT in patients with GBM. In our group, median survival for those receiving 60？Gy with Temozolomide compared favourably to the combined therapy arm of the largest randomised trial of chemoradiation versus radiation to date (17.4 months versus 14.6 months). We propose that IMRT should be considered as an alternative to 3DCRT for patients with GBM. 1. Introduction Gliomas are the most common primary brain tumour, and GBM accounts for up to 70% of cases. The prognosis is poor, and while adjuvant cranial irradiation has been shown historically to significantly improve survival rates [1, 2], the treatment of patients with GBM remains challenging. The median survival for patients with GBM treated with postresection radiation alone has been of the order of 11 months. Recent advances in chemotherapy have increased overall survival to around 14.6 months with 26% survival at 2 years with the addition of concurrent and adjuvant Temozolomide [3]. This improvement in survival is even greater for those patients with favourable molecular profiles. In the phase 3 trial from the European Organisation for Research and Treatment of Cancer published by Hegi et al., there was a 46% 2 year survival for those patients who had epigenetic silencing via methylation of the promoter of the gene which metabolises Temozolomide (O-6-methylguanine-DNA-methyltransferase, MGMT) [4]. This survival benefit was maintained on long-term followup [5]. While these advances in systemic treatment, cancer genomics, and the availability of highly conformal treatments such as IMRT are encouraging, they have not fully translated into clinical practice
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