3510 - Palliative Radiotherapy within the Last 30 Days of Life: A Multi-Site Review of Practice Patterns

Purpose/Objective(s): Palliative radiotherapy (RT) alleviates cancer morbidities. However, symptomatic improvement can take weeks and protracted RT compromises both end-of-life quality and healthcare resource allocation. We examined the end-of-life patterns of palliative RT in our institutional network.

Materials/Methods: All patients who died =30 d from the start of palliative RT were identified at a tertiary care hospital and 4 community centers between Jan 2016 and Jun 2024. Clinical characteristics, RT information, and other services from the EHR were integrated in Palantir Foundry. Among patients who had been prescribed the RT fractionations 30 Gy/10, 20 Gy/5, or 8 Gy/1, frequencies were compared across patient characteristics using Fisher’s exact test. Survival comparisons were performed using Cox regression.

Results: There were 1180 patients who died =30 d after starting the select RT regimens. 30 Gy/10 (54%) was the most common regimen, followed by 20 Gy/5 (38%) and 8 Gy/1 (8%). Distribution did not differ by age, sex, or ethnicity/race. ECOG =3, receipt of systemic therapy, ED visit, and ICU admission =14 d of RT independently conferred worse survival (P_multivar<0.05) yet still favored longer fractionation regimens (Table). Even among those who died =14 d after starting RT, 30 Gy/10 remained the most common regimen (50%). 20 Gy/5 was the most common regimen for palliating GI, head & neck, and hematologic cancers, as well as for targets in the chest, pelvis, and bones. The proportions of 20 Gy/5 and 8 Gy/1 increased over time (P=0.02), though 30 Gy/10 predominated absolute utilization.

Conclusion: The majority of patients who died <14 d and =30 d after starting palliative RT received 30 Gy/10. Development of modern prognostic tools will be essential to accurately guide shorter palliative RT fractionation schedules for patients near the end of life.