Jenkins, Mikayla

145 Background: Palliative radiation treatment (pRT) is used for symptomatic bone metastases (mets). Several fractionation schedules show equal efficacy for pain relief, and ASTRO’s Choosing Wisely recommends 8Gy x1, 4Gy x5, or 3Gy x10. This study aims to investigate the cost implications of pRT for bone mets. Methods: Patients (Pts) treated with pRT for bone mets at Mayo Clinic from 2007 - 2016 were included in this study. Costs for all services were subdivided into RT and total costs at 30 & 90 days (30D & 90D). Standardized costs were obtained from the Mayo Clinic Cost Data Warehouse and Medicare reimbursements were assigned to all services with cost to charge adjustments and 2017 GDP Implicit Price Deflator for inflation. Cost means were compared via the Kruskal-Wallis test. Results: 538 pts were treated with pRT, 124 receiving 8Gy x1, 204 receiving 4Gy x5, and 210 receiving 3Gy x10. Pts with breast and prostate cancer were most likely to be treated with 3Gy x10 and pts with GI and lung cancer were most likely to be treated with 8Gy x1. RT costs at 30D were $1,497, $1,891, and $1,982 (p=0.03) and RT costs at 90D were $2,602, $2,753, and $3,032 (p=0.08) for initial RT regimens of 8Gy x1, 4Gy x5, and 3Gy x10. Total costs of care at 30D were similar from $15,969 - 17,687 (p=0.6) and total costs at 90D were similar from $22,361 - 23,219 (p=0.7) between arms. A total of 23%, 28%, and 39% of pts were alive 2 years following pRT from each arm (p=0.07). Conclusions: This is the first study of its kind to analyze actual treatment costs for the three most common pRT regimens in bone mets. Single fraction RT was most used for pts with poor prognoses and was associated with lower RT costs at 30D, but similar RT costs at 90D, possibly due to retreatment. RT choice had no impact on overall costs of care at 30D or 90D. pRT remains of high value, representing only 11-13% of total costs.[Table: see text]

126 Background: Palliative radiation treatment (pRT) is a common and effective treatment for patients with symptomatic bone metastases. However, patients receiving RT for bone metastases often may have a poor performance status and are more likely to experience toxicity during or after treatment. This study aims to investigate the number and type of toxicity event occurring during or after pRT for bone metastases. Methods: Patients treated with RT for bone metastases at Mayo Clinic from 2007 to 2016 were included in this study. Demographic, disease, treatment, and toxicity information were collected. Specifically, toxicity events were identified as emergency department (ED) visits and inpatient hospitalization (IH) within 90 days, breaks in treatment >4 days, and excessive 30 day financial toxicity defined as standardized Medicare costs >1 standard deviation above the mean. RT treatment was compared by dose and fractionation via descriptive statistics. Results: A total of 538 patients treated with pRT were identified, 124 receiving 8Gy x1, 204 receiving 4Gy x5, and 210 receiving 3Gy x10. Patients with breast and prostate cancer were most likely to be treated with 3Gy x10 and patients with GI and Lung cancer were most likely to be treated with 8Gy x1. A description of the patient characteristics and toxicities are shown in Table 1. For 8Gy x1, 4Gy x5, and 3Gy x10 breaks in treatment were rare (0%, 2%, and 3.3%), ED visits (15%, 24%, & 28%), IH (12%, 23%, & 19%), and financial toxicity (13%, 18%, & 21%) were common. A total of 22.6%, 27.5%, and 38.6% of patients were alive two years following pRT from each group. Conclusions: Toxicity during or shortly after pRT of bone metastases is common. This study confirms that additional steps should be taken to monitor and mitigate toxicity in this vulnerable patient group. [Table: see text]