OBJECTIVES: This study describes the role of treatment intent (curative versus palliative) on toxicity events, treatment breaks (>4days), emergency visits and hospital admissions. Factors associated with toxicity and admissions 30-day after the end of treatment were predicted.

METHODS: Retrospective review of 1,676 cancer patients' who had curative (n=1313) or palliative (n=363) radiotherapy between 2012-2016 at Mayo Clinic Florida, USA. Toxicity was defined as provider-documentation of (IV Fluids, blood transfusion, weight loss>10%, Lymphedema consultation, Speech medicine consultation, an order of narcotics, or an order of Pentoxifylline, Bevacizumab, or Dexamethasone as an indicator of osteoradionecrosis, radionecrosis, cerebral edema or radiation necrosis) in the following treatment visit. Univariate and multivariate analyses were used to determine the role of treatment intent with our selected measures.

RESULTS: More than 75% palliative patients experienced a toxicity during radiotherapy, a significantly higher rate than those receiving curative (54.4%;p<0.01). Per disease sites, toxicity had the highest rate in head and neck (H&N) (91.8%), gastrointestinal (81.3%), and lung (69.2%) cancers. The most common toxicities were Narcotic use for H&N (84.8%) and IV fluids for gastrointestinal (56.4%) and breast (34.9%). Curative patients had more treatment breaks (9.2% vs. 3.9%;p<0.01), while palliative patients had more emergency visits during treatment (32.8% vs.18.4%;p<0.01) and admissions 30-days after the end of treatment (15.4% vs.6.2%;p<0.01). In multivariable logistic regression, a toxicity had greater odds to occur among patients receiving palliative radiation (OR=2.27,95%CI=1.49-3.44), radiation with chemotherapy (OR=3.10,95%CI=2.31-4.16) and those in more severe cancer stages (stage 3: OR=2.40,95%CI=1.63-3.53; stage 4: OR=2.86,95%CI=1.92-4.26). A 30-day hospital admission had greater odds to occur among patients with Genitourinary cancers (OR=1.05,95%CI=1.00-1.12), stage 3 cancer (OR=1.04,95%CI=1.02-1.08), and those who had a toxicity (OR=1.03,95%CI=1.02-1.06) or an emergency visit (OR=1.26,95%CI=1.22-1.31) during their treatment course.

CONCLUSIONS: Toxicity and adverse outcomes were relatively common in radiotherapy, with significantly higher rates in palliative treatment and among patients with certain cancer sites and stages.