NCOG-31. TUMOR TREATING FIELDS: REAL-WORLD SURVIVAL AND QUALITY OF LIFE OUTCOMES ON THE XCELSIOR PLATFORM

Abstract

Abstract OBJECTIVE xCures operates a direct-to-patient, real-world evidence platform according to the nationwide observational research protocol XCELSIOR (NCT03793088), which aggregates medical data in an FDA-compliant electronic database. We used this platform to analyze advanced registry survival and Quality of Life (QoL) outcomes associated with the use of Tumor Treating Fields (TTFields) for treatment of high grade central nervous system (CNS) tumors. METHODS XCELSIOR participants with high grade CNS tumors were invited weekly to complete the EuroQol 5-Dimension (EQ-5D-5L) QoL questionnaire over the course of one year. A EuroQol-endorsed model was used to estimate health state utilities from patients’ EQ-5D responses. The participating patients’ clinical data was accessed from the XCELSIOR platform to enable study of clinical factors and survival outcomes. RESULTS 225 patients with high grade CNS tumors in total completed at least one EQ-5D questionnaire. 88 patients (39%) had ever used TTFields and 58 of these patients (26%) were currently using TTFields. Patients currently using TTFields had significantly higher average health state utility estimates compared to non-users (p=.00183), with a mean improvement in utility of .14 (SE=.04), indicating significantly higher overall QoL in TTFields users. Mortality events were recorded for 40 participating patients, 14 (35%) of which had used TTFields. From these 40 events the mean/median overall survival (OS) for patients who had used TTFields was 23.39/20.15 months vs 15.77/12.72 months for patients who had not used TTFields, showing significantly higher average OS in patients who had used TTFields (p=.04139). CONCLUSION The XCELSIOR platform has enabled the study of real-world clinical and QoL outcomes for patients with CNS tumors. The results show that use of TTFields is associated with improved survival as well as improved overall Quality of Life for patients in a real-world setting, corroborating results seen in trial settings as well as results seen in other real-world studies.