Use of Radiation Within the Last Year of Life Among Cancer Patients

Abstract

In a large single institution, we examined use of radiation (RT) within the last year of life. We hypothesized that as palliative RT (PRT) has been well studied in patients with life expectancies of 6 weeks or longer, PRT use would be constant over the remaining year of life, except for the last 30 days, when use would decline. All patients seen at a single institution who died between 10/1/2014 and 9/30/2015 (n = 1187), had at least three evaluation and management visits within the last year of life (n = 880), and had a cancer diagnosis (n = 870) were included in this study. Records from claims data (clinical, demographics) and RT treatment (start date, treatment intent, ICD9 code, number of fractions) were extracted and linked. Over the last 365 days of life, we evaluated RT utilization by intent (curative vs palliative) and by indications (ICD9). Aside from descriptions of clinical characteristics, which were by patient, analyses were performed by radiated site. Among 870 cancer patients, 280 (32.2%) underwent RT to 415 sites within the last 365 days of life (RT365). Utilization decreased to 23.3% and 8.2% in the last 180 and 30 days of life, respectively. RT365 patients were slightly younger at death (median, 61 vs 64 years) and had a higher proportion of lung (17.1% vs 10.5%), sarcoma (7.9% vs 2.9%), and transplant (11.1% vs 4.4%) disease groups. In the last 365 days of life, 25% of sites were radiated with curative intent. RT utilization for curative sites was constant across the last 365 days of life (12, 6, and 1 month(s) from death: 9.6%, 7.7%, and 7.7%, respectively). In contrast, RT for palliative sites increased more rapidly closer to death (12, 6, and 1 month(s) from death: 2.9%, 5.8%, and 14.8%, respectively). Based on ICD9 coding, treatment of bone metastases and utilization of single-fraction RT for bone metastases increased closer to death (Table 1). The originally planned RT treatment course was not completed in 31 of 311 (9.9%) palliative sites. Stopping treatment midcourse was higher among patients that started RT in the inpatient versus outpatient setting (13.6% vs 9%).Abstract 1113; Table 1Days from death (n = sites)30 days (n = 47)31-180 days (n = 164)181-365 days (n = 100)Proportion of palliative sites treated for bone metastases (ICD9 198.5)48.9%38.4%37.0%Number of fractions prescribed 152.2%28.6%32.4% >1 to 526.1%38.1%32.4% >5 to 1017.4%30.2%24.3% >10 to 154.3%3.2%10.8% Open table in a new tab Among a cohort of cancer patients regularly seen and treated at a single, high-volume institution, PRT appears to be disproportionately utilized closer to death with an increasing proportion of radiated sites being bone metastases. This may be secondary to increased symptoms from advanced cancer toward the end of life. As patients with very poor prognosis (e.g. within 30 days of death) are generally not included in RT clinical trials, further studies are warranted to assess whether PRT for bone metastases at the end of life is efficacious.