CTNI-40. PSYCHOLOGICAL DOMAINS CORRELATE WITH ADHERENCE IN TTFIELDS TREATMENT OF GLIOBLASTOMA

Abstract INTRODUCTION Adherence is critical to the success of the treatment with Tumor Treating Fields (TTFields) for Glioblastoma Multiforme (GBM). Previously found factors influencing treatment adherence in general are social support, belief in the efficacy of treatment, communication with physicians, anxiety, and depression. We propose those five factors predict adherence to TTFields treatment since, to our knowledge, no systematic data exists for this treatment. METHODS We conducted a longitudinal study and included 25 patients with newly diagnosed GBM who received treatment with TTFields. Participants were invited to take part in six structured interviews, each four weeks apart, during their treatment with TTFields, assessing the five factors expected to influence treatment adherence over time. RESULTS We found a significant impact of communication, anxiety, and depression on treatment adherence with TTFields. Furthermore, also the time point during treatment (days of treatment) was significantly related to adherence. Better physician communication and a higher level of anxiety were associated with higher adherence and higher depression with less adherence. A higher belief in efficacy showed a trend toward significantly improving treatment adherence. When results were separately compared for early, middle, and later 90-day treatment phases, factors seemed to be differentially influential, with belief in efficacy being significantly relevant in the first, efficacy, communication, and anxiety in the second, and depression in the third phase of treatment with TTFields. CONCLUSIONS Our findings not only confirm the predictive role of psychosocial factors in treatment adherence but also provide specific targets for psychological interventions. This suggests that by addressing these factors, healthcare providers can potentially increase treatment adherence among GBM patients. Moreover, our results indicate that these interventions may be most effective when tailored to the specific phase of treatment, offering a practical approach for healthcare providers.