2599 - Exploring the Ef?cacy and Optimal Duration of Tumor Treating Fields (TTFields) in Newly Diagnosed Who Grade 4 Gliomas: A Multi-Institutional Analysis
Presenter(s)
G. Han1, M. Zhai2, Q. Li3, L. Liang4, Y. Huang5, Y. Zhong5, G. Hu6, J. Huang7, and Y. Wang8; 1Department of Radiation Oncology, Hubei Cancer Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China, Wu Han, China, 2Department of Radiation Oncology, Hubei Cancer Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China, Wuhan, China, 3Tongji hospital, Tongji medical college, Huazhong university of science and technology, Wuhan, China, 4Radiation Oncology Center, Huashan Hospital, Fudan University, Shanghai, China, 5Department of Radiation and Medical Oncology, Zhongnan Hospital, Wuhan University, Wuhan, China, Wuhan, China, 6Department of Oncology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China, Wuhan, China, 7Cancer Center, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China, 8Department of Radiation Center, Huashan Hospital, Fudan University, Shanghai, China., Shanghai, China
Purpose/Objective(s): Concurrent chemoradiotherapy followed by adjuvant temozolomide (TMZ) ± tumor treating fields (TTFields) is the standard first-line treatment for newly diagnosed WHO grade 4 gliomas. The clinical outcomes of these patients receiving TTFields concurrent chemoradiotherapy and adjuvant TMZ, with or without TTFields maintenance treatment, and the optimal application time of TTFields, remain unclear and warrant further study.
Materials/Methods: A multi-center retrospective data analysis of patients with newly diagnosed WHO grade 4 gliomas receiving TTFields concurrent chemoradiotherapy between January 2020 and June 2024 at five hospitals in China. Kaplan-Meier plots, log-rank tests, and univariate and multivariate Cox regression models were performed for survival analyses of progression-free survival (PFS) and overall survival (OS).
Results: A total of 87 patients were analyzed; 30 received TTFields/radiotherapy/TMZ followed by adjuvant TMZ (CRT group), and 57 received TTFields/radiotherapy/TMZ followed by adjuvant TMZ/TTFields (CRT-T group). With a median follow-up of 37.1 months, there was no significant difference in PFS (15.4 months vs. 12.4 months, HR: 0.93, p= 0.78) and median OS (17.0 months vs. 19.4 months, HR: 1.22, p= 0.47) between CRT and CRT-T groups. The Cox regression analysis found that age and the usage time of TTFields were significantly associated with PFS and OS. The usage time of TTFields for longer than 12 months significantly improved patient survival without increasing TTFields-related scalp toxicity.
Conclusion: As the first real-world study comparing the survival benefits of TTFields concurrent chemoradiotherapy followed by adjuvant TMZ, with or without TTFields maintenance therapy in newly diagnosed WHO grade 4 gliomas, no survival differences were observed between CRT and CRT-T groups, however, compared with the historical data of treatments without TTFields, the addition of TTFields can indeed bring benefits in patients with WHO grade 4 gliomas. Besides, the duration of TTFields use (especially beyond 12 months) was positively associated with PFS and OS and did not increase treatment-related toxicity. These results need to be validated in larger prospective studies.