P01.168 International Inconsistency in management of recurrent glioblastoma creates challenges in developing new clinical trials

Abstract

BACKGROUND: The optimal choice and timing of treatment for recurrent GBM is unclear. Understanding the effect of further treatment on survival and quality of life, compared with best supportive care, is a top 10 clinical priority for the UK neuro-oncology community. Prior to developing a clinical trial to address this uncertainty we surveyed the neuro-oncology community to understand current variations in practice. METHODS: A google survey was designed to collect data. The Society of British Neurosurgeons, European Association of Neuro-oncology and a UK oncology network circulated the survey. RESULTS: 233, responses were received from clinical/medical oncologists, neurosurgeons, neurologists and radiologists. Responders were from UK (45), rest of Europe (123) and outwith Europe (65). 40% of responders reduced the frequency of radiological surveillance to 6 monthly in second year after diagnosis. There were variations in radiological definition of recurrence; 45.1% local recurrence of enhancing disease, 21.0% MR spectroscopy, 21.4% MR perfusion, the remainder used PET. Only 64% respondents presented every case of recurrence for multidisciplinary review. 45% of respondents did not consider a maximum age in deciding a therapeutic strategy. 43.0% had a minimum KPS of 70, 27.5% a minimum of 80.53.4% did not consider MGMTmethylations status important. Only 50.3% of respondents thought repeat surgery should be undertaken only if more than 90% resection is anticipated. 50.0% of respondents had no minimum time to have elapsed since the first operation before consideration of reoperation. 40.2% will consider repeat surgery even if no further oncological treatment available. 41.0% will consider repeat temozolomide as second-line option after repeat surgery, 33.0% will consider PCV, 18.0% lomustine. 70% respondents would consider re-irradiation. CONCLUSION: The significant variation in management of recurrent disease refects a lack of evidence-base treatment guidelines. This variation complicates design of clinical trials and consensus guidelines would help future trial design.