A1: A Review of Local Outcomes in Glioblastoma in Cornwall with Respect to Performance Status, Age and MGMT Methylation Status.

Stuart Walter1,John McGrane1,Peter Rimmer2,Roy Powell3,Richard Ellis1,Carolyn Campbell1,Toby Talbot1

1Oncology Depatment, Royal Cornwall Hospital, Truro, UK,2Cheltenham General Hospital, Cheltenham, UK,3Royal Devon & Exeter Hospital, Exeter, UK

Presenting date: Monday 2 November
Presenting time: 12.20-13.10

Background

Glioblastoma (GBM) is an aggressive cerebral malignancy with a poor prognosis and limited treatment options. O6-methylguanine-DNA methyltransferase (MGMT) is a repair protein that, when methylated, is thought to confer an improved response to temozolomide, a chemotherapy agent used as standard care in GBM.1 In a disease with such a short life-expectancy careful patient selection is essential to maximise both quantity and quality of life. Our aim was to assess whether it is possible to predict those who will benefit most from treatment in GBM.

Method

We performed a retrospective study of all patients treated at The Royal Cornwall Hospital with a diagnosis of GBM from 2003-2013 (n=106). Data was collected for age, performance status, MGMT methylation, treatment received, toxicity and overall survival. This was then analysed with the primary outcome of overall survival. COX regression analysis was used to measure the significance of the outcomes and Kaplan-Meier charts were produced.

Results

Median survival was 7 months (95% CI 4.9 to 9.2). Patients were divided into four age groups; 18-56, 57-62, 63-68 and 69 - 70 years. These demonstrated significant improvement in survival with younger age. Performance status followed this pattern but was not significant on analysis. Chemo-radiotherapy proved to be the most effective treatment at improving survival with palliative radiotherapy (30Gy in 6#) being not significantly different from palliation alone.The most marked and significant survival benefit was seen with MGMT methylation with non-methylated MGMT faring less well.

Conclusion

Our experience at the Royal Cornwall Hospital corroborates with previous studies; that methylation of MGMT predicts an improved outcome.1 A strong inverse correlation was also found with age. Therefore in elderly or co-morbid patients the balance of risk-to-benefit suggests it may often be better to pursue symptomatic relief alone. MGMT status can assist in the decision making process when discussing treatment intent.