Practice Patterns Related to Mitigation of Neurocognitive Decline in Patients Receiving Whole-Brain Radiation Therapy.

PURPOSE/OBJECTIVE(S) Whole brain radiation therapy (WBRT) is often employed as an effective treatment to palliate symptoms, improve intracranial control, and potentially improve survival for patients with brain metastasis, although it is also known to have deleterious cognitive effects. Despite multiple trials having identified strategies to help mitigate neurocognitive decline after WBRT, we hypothesized there may be barriers to integrating these techniques into routine clinical practice. The aim of this study was to characterize national practice patterns related to neurocognitive preservation strategies utilized during WBRT. MATERIALS/METHODS We conducted an online survey of all American Society for Radiation Oncology-registered radiation oncologists (RO), excluding trainees, regarding their practice patterns and attitudes towards employing memantine, an N-methyl-D-aspartate receptor antagonist, and hippocampal avoidance (HA) whole brain radiotherapy. Both techniques have been shown to reduce cognitive decline when compared to conventional whole brain radiotherapy in patients undergoing WBRT. The Pearson χ2 tests for categorical variables or student's t-test for continuous variables were used to assess associations between provider characteristics and prescribing of either memantine or HA. All statistical tests were two-sided and a P-value < 0.05 was considered statistically significant. RESULTS A total of 4,408 radiation oncologists were invited to participate in the survey, of whom 424 (9.6%) completed the survey. Among respondents, 79.6% reported having offered memantine, 72.6% HA, and 63.1% both for any of their patients undergoing WBRT. Nearly half (47.4%) of RO offered memantine for most (76-100%) of their WBRT patients. Common reasons for not offering memantine included limitations of current evidence (36.8%) as well as concerns about adverse effects (23.0%) and medication cost (23.0%). Most RO offered HA (66.5%) to a minority (1-50%) of their WBRT patients. Common reasons for not offering HA included resource-intense treatment planning and treatment delay (43.6%), concern about obtaining insurance approval (38.5%), and having no patients who met their criteria for HA (22.2%). RO with were more likely to prescribe memantine (P < 0.001), while HA was more likely prescribed by central nervous system specialists (P < 0.001) and RO in academic settings (P = 0.03). CONCLUSION Our survey suggests that the majority of respondents offer approaches for neurocognitive preservation during WBRT for their patients. However, universal and consistent adoption of these approaches may be limited by current evidence and logistical hurdles to administration. Further efforts are needed to broaden education and reduce barriers among RO in order to improve implementation of neurocognitive-sparing techniques in patients undergoing WBRT. AUTHOR DISCLOSURE V. Jairam: None. H.S. Park: Employee; Yale School of Medicine. J.B. Yu: Consultant; Augmenix / Boston Scientific. Advisory Board; Galera pharmaceuticals. R.S. Bindra: None. J.N. Contessa: None. K.R. Jethwa: Honoraria; Radoncquestions.com, LLC.