Defining end-of-life in glioblastoma multiforme: a systematic review

Abstract

Background: Glioblastoma multiforme is an incurable tumor with a poor prognosis, characterized by a median overall survival of only 15 months. A difficulty lies in identifying the end-of-life phase for individuals confronting both an incurable cancer and progressive neurological deterioration. The lack of a precise definition of this phase affects the reliability of research results on this topic. Purpose: To determine how the end-of-life phase is characterized and conceptualized in people with glioblastoma, and to identify precise identification criteria for future research and clinical application. Design: Systematic review and narrative synthesis. Data sources: Electronic databases including PubMed, Web of Science, Science Direct, and Psych Info were systematically searched for relevant articles published until January 2025. Eligible studies included adults diagnosed with glioblastoma in the terminal palliative phase, along with their family caregivers or healthcare professionals. Quality assessment was performed. Results: Eighteen studies fulfilled the inclusion criteria, yet only eight provided definitional elements. Notably, these definitions varied considerably and lacked consensus. Furthermore, none of the studies referred to validated scales or scores for determining the end-of-life phase, nor did they aim to develop such measures. Conclusion: The lack of a standardized end-of-life definition in glioblastoma multiforme complicates clinical decision-making and research. A Delphi-based approach involving consultation with experts in the field is deemed imperative. A consensus is essential to improve prognostic accuracy, guide evidence-based interventions, optimize resource allocation, and foster ethical reflection.