Persistent use of extended fractionation palliative radiotherapy for medicare beneficiaries with metastatic breast cancer, 2011 to 2014

Introduction:With no evidence to support extended radiation courses for the palliation of bone metastases, multiple guidelines were issued discouraging its use. We assessed contemporary use and cost of prolonged palliative radiotherapy in Medicare beneficiaries with bone metastases from breast cancer.Methods:We conducted a retrospective, longitudinal study of palliative radiotherapy use among fee-for-service Medicare beneficiaries with bone metastasis from breast cancer who underwent palliative radiotherapy during 2011 to 2014. Patients were categorized according to the number of days (fractions) on which they received palliative radiotherapy: 1, 2 to 10, 11 to 19, or 20 to 30. We examined the association of clinical, demographic, and provider characteristics with the use of extended (≥11 fractions) or very extended (≥20 fractions) fractionation with logistic regression models. We also compared the cost of different fractionation schemes from the payer perspective.Results:Of the 7547 patients in the sample (mean age, 71 y), 3084 (40.8%) received extended fractionation. The proportion of patients receiving 11 to 19 (34.7% in 2011 and 28.1% in 2014, trend P<0.001) and 20 to 30 treatments (10.3% in 2011 to 9.0% in 2014, trend P=0.07) decreased modestly over time. Patients with comorbidities were less likely to undergo extended fractionation (34.4% for ≥3 comorbidities vs. 44.9% for 0 comorbidities; adjusted odds ratio 0.67 [95% confidence interval, 0.58-0.76]). Patients treated at free-standing practices were more likely to undergo extended fractionation (47.9%) compared with those treated at hospital-based practices (37.3%, P<0.001; adjusted odds ratio, 1.49 [95% confidence interval, 1.35-1.65]). The mean cost of treatment varied from $633 (SD $240) for single-fraction treatment, to $3566 (SD $1349) for 11 to 19 fractions, to $6597 (SD $2893) for 20 to 30 fractions.Conclusion:The use of prolonged courses of palliative radiotherapy among Medicare beneficiaries with breast cancer remained high in 2011 to 2014. The association between free-standing facility status and use of extended fractionation suggests that provider financial incentives may impact choice of treatment.