Radiotherapy has been shown to prolong survival in glioblastoma and temozolomide improves survival further in selected patients. Older and poorer performance status patients have equivalent outcomes with 3 versus 6 weeks of radiotherapy. Due to strict entry criteria and sometimes geographic constraints clinical trials commonly enrol patient groups that may not be representative of the broader population. The aim of this study was to review population-based outcomes for glioblastoma focussing on radiotherapy treatment.
The Evaluation of Cancer Outcomes (ECO) Registry records clinical and treatment information on all newly diagnosed cancer patients in the Barwon South West Region (BSWR) of Victoria encompassing approximately 380,000 people. This study analysed patterns of care and outcomes for all glioblastoma patients diagnosed in the BSWR from 2009-2014.
There were 111 patients diagnosed in the BSWR during the 5 year period. The median age at diagnosis was 67. Radiotherapy was given to 81 patients (73%) and dose was split into high dose (>50 Gy, median 60 Gy, HD), mid dose (35-50 Gy; median 40 Gy, MD) and low dose (<35 Gy, median 20 Gy, LD). There were 55, 16 and 10 patients in the HD, MD and LD groups respectively. The median survival of the HD, MD and LD groups was 16.0, 7.5 and 3.0 months respectively and the median ages were 61.3, 73.5 and 71.9 years. Thirty patients (27%) had no record of receiving radiotherapy, with a median survival of 2.5 months and median age 70.5 years.
This population based study has shown that approximately two thirds of patients receive HD or MD radiotherapy and have survival in line with the major published trials. Further analysis of the patients with no record of radiotherapy and short survival may help determine if there are barriers to care potentially impacting on outcomes.