Funding Acknowledgements Type of funding sources: Public Institution(s). Main funding source(s): University of Toronto Background Established guidelines discuss ICD deactivation and end of life care in ICD patients. A previous study has suggested that 45% of patients with an ICD and do not resuscitate order have not discussed ICD deactivation. In patients receiving radiation therapy for cancer ICD deactivation should be discussed given the life limiting nature of cancer, however it is unclear how frequently this topic is discussed in clinical practice. Objectives To report on the frequency of discussions of ICD deactivation in a population of patients receiving radiation therapy for cancer. Methods Our hospital is a large regional cancer and cardiac center in Canada. Consecutive patients of our institution presenting to our ICD clinic for ICD checks prior and during receipt of radiation therapy between 2005 and 2019 were included (n=43). Electronic medical records were reviewed to determine demographics, clinical characteristics, documentation of discussions on ICD deactivation, and survival at 1-year. Results The cohort was predominantly male (84%), with a primary prevention ICD (65%) without resynchronization capacity (74%). Discussions on ICD deactivation with subsequent deactivations occurred in 12 (28%) patients. During a median follow-up of 4 years 25 patients died, with 28% of these patients dying within 2 years of the ICD clinic encounter. Discussions on ICD deactivation were more frequent in patients who received a palliative care consultation. Conclusions End of life conversations regarding ICD deactivation in patients undergoing radiation therapy for cancer are rare. Collaboration with palliative care teams may facilitate conversations on ICD deactivation during this opportune time.