Time toxicity faced by patients with advanced cancer across primary cancer sites.

268 Background: Time toxicity, defined as the burden of time for patients interacting with the health care systems, is particularly important for patients with limited life expectancy. Little is known about the relative impact of time toxicity among different cancer types at the end of life. This study examines median contact days for inpatient, outpatient, and home health services among different primary cancer types for patients with advanced cancer with limited prognosis. Methods: A retrospective cohort analysis was performed on patients with advanced (stage 4) cancer who died within one year of diagnosis at Kaiser Permanente Northern California between January 1, 2015, and June 30, 2023. Time toxicity was defined as comprehensive contact days with healthcare system over the course of patients’ survival period between cancer diagnosis and death (i.e., contact days divided by survival or contact %). Types of contact included institutional stay (emergency department visit, hospitalization, skilled nursing facility, rehabilitation); outpatient visits (ambulatory care, labs, imaging); and in-home care (home-health, home hospice, telephone and virtual visit). The study quantified overall median contact % and contact % by specific care settings, stratified by cancer primary site. Results: The study included 10102 patients. The median age at diagnosis was 74 years with 47% female. Patients were predominantly white (65%), followed by Asian (12%), Hispanic (12%), and black (8%). The median Elixhauser comorbidity score was 4. With the exception of head and neck cancers, most cancers had higher contact % near diagnosis and at end of life (U-shaped curve). Head and neck cancers had the highest percent of patients undergoing surgery (36%) and radiation (52%), which may explain its sinuosity-like curve with a rapid increase of weekly contact % after diagnosis (a small peak), followed by rapid decrease and another increase by the end of their life. Survival days were comparatively long for head and neck cancers (158 days, IQR: 84-265) and short for thoracic (80 days, IQR: 35-166) and upper gastrointestinal cancers (80 days, IQR: 38-173). Malignant hematology patients had notably higher comprehensive contact % (74%, IQR: 47-100) which was driven primarily by emergency room department visits and hospital stays (p<0.001 for all contact types). Conclusions: The study highlights the high burden of time toxicity in patients with advanced cancer with limited prognosis. The significant variations in time toxicity among different cancer types, especially in malignant hematology and head and neck patients, emphasize the need to tailor goals of care discussions for patients with cancer at the end of life. By focusing on reducing unwanted time toxicity, healthcare providers can enhance the quality of life for patients with cancer, ensuring more efficient and patient-centered care delivery.