INNV-30. RETROSPECTIVE ANALYSIS OF TTFIELDS IN PATIENTS WITH HGG BASED ON THE CRITERIA OF 2021 WHO CNS5

Abstract

Abstract PURPOSE High-grade glioblastoma (HGG) was highly malignant and had a poor prognosis, with an overall median survival time of only 15 months. Tumor-Treating Fields (TTFields) has been approved for the newly diagnosed glioblastoma (GBM), and more clinical evidence is needed for its use in HGG. The aim of this study was to analyze the efficacy and safety of TTFields in patients with HGG in our center. METHODS We analyzed baseline characteristics, efficacy, and safety data of 27 newly diagnosed HGG patients treated with TTFields for at least four weeks from January 2020 to February 2022 at West China Hospital of Sichuan University. All the pathological grades were diagnosed based on the 2021 World Health Organization Classification of Tumors of the Central Nervous System (2021 WHO CNS5) criteria. RESULTS Twenty-one patients (77.78%) were diagnosed as grade 4. Among them, the percentage of gross total resection was 81.48%, and MGMT promoter methylation was 51.85%. The median interval from surgery to TTFields initiation of treatment was 2.47 months (95% CI, 1.47-10.37). The median follow-up time was 12.47 months (95% CI, 8.6-15.03). The 12-month PFS rate and 12-month OS rate were 70.73% and 90.24%, respectively. Median PFS and OS have not been reached. The median compliance of patients wearing TTFields was as high as 95%, and their associated adverse events were patch-induced rash and ulcers, all of which were grade 1 ~ 2. CONCLUSIONS This study is the first to define HGG patients with the 2021WHO CNS5. TTFields were observed in this retrospective analysis to improve patients’ 12-month PFS rate and OS rate. Adherence was much higher than that reported in clinical studies, and safety remained good. More extended Survival data would be updated by further follow-up.