Incidence and radiotherapy treatment patterns of complicated bone metastases

Background: Despite the encouraging results of the SCORAD trial, single fraction radiotherapy (SFRT) remains underused for patients with complicated bone metastases with rates as low as 18-39%. We aimed to evaluate the incidence and treatment patterns of these metastases in patients being referred to a tertiary centre for palliative radiotherapy. Materials and methods: We performed a retrospective review of all bone metastases treated at our centre from January 2013 until December 2017. Lesions were classified as uncomplicated or complicated. Complicated was defined as associated with (impending) fracture, existing spinal cord or cauda equina compression. Our protocol suggests using SFRT for all patients with complicated bone metastases, except for those with symptomatic neuraxial compression and a life expectancy of >= 28 weeks. Results: Overall, 37 % of all bone metastases were classified as complicated. Most often as a result of an (impending) fracture (56 %) or spinal cord compression (44 %). In 93 % of cases, complicated lesions were located in the spine, most commonly originating from prostate, breast and lung cancer (60 %). Median survival of patients with complicated bone metastases was 4 months. The use of SFRT for complicated bone metastases increased from 51 % to 85 % over the study period, reaching 100 % for patients with the poorest prognosis. Conclusions: Approximately 37 % of bone metastases are classified as complicated with the majority related to (impending) fracture. Patients with complicated bone metastases have a median survival of 4 months and were mostly treated with SFRT.