Palliative radiotherapy for bone metastases at the end of life in Victoria

To the Editor: Palliative radiotherapy is effective for symptomatic management of bone metastases in cancer patients. However, it may take 2–4 weeks after completion of radiotherapy to achieve maximal clinical response.1 Radiotherapy can be delivered as a single fraction treatment (SFRT), or over a more protracted course of multifraction treatment (MFRT).2 Randomised trials have consistently shown that SFRT and MFRT provide equally effective symptom control,3 and SFRT is associated with lower medical and societal cost,4 allowing for better health services utilisation. Hence, in patients with poor prognosis, the use of SFRT over MFRT should be encouraged to minimise the time patients spend on treatment at the end of life without compromising efficacy.

Using the population‐based Victorian Cancer Registry data linked to the Victorian Radiotherapy Minimum Data Set, we evaluated the use of SFRT for bone metastases at the end of life. The study sample included all cancer patients who received radiotherapy for bone metastases between 2013 and 2016, and died within 30 days of commencing radiotherapy. The primary outcome was SFRT use and the associated factors. The Cochrane–Armitage test for trend was used to evaluate temporal changes in SFRT use over time. Logistic regression was used to evaluate factors associated with SFRT use; variables with a P value below 0.1 in univariate analyses were included in multivariate model, which employed the robust standard error, with analyses clustered on patient identifiers to allow for clustering of patients who had multiple courses of radiotherapy. The study was approved by the Austin Health Human Research Ethics Committee (LNR/18/Austin/34).

A total of 1069 patients received 1359 courses of radiotherapy for bone metastases at the end of life, of which 396 courses (29%) were SFRT, and 963 (71%) were MFRT (Box). There was no significant change in SFRT use over time: from 30% in 2013 to 32% in 2016. SFRT was more commonly used closer to death: 49%, 29% and 25% of radiotherapy courses delivered within 7 days, 8–14 days, and 15–30 days of death, respectively. There were large institutional provider variations in SFRT use: 33% and 19% of radiotherapy delivered in public and private institutions, respectively. In multivariate analyses, the site of bone metastases, time between radiotherapy and death, and treatment institution type were independently associated with SFRT use.

Overall, in this large Victorian population‐based study, less than one in three courses of radiotherapy for bone metastases at the end of life were SFRT, and about one in two courses of radiotherapy delivered in the last week of life were MFRT, meaning that these cancer patients spent multiple days in their final week of life receiving radiotherapy. Acknowledging that estimation of prognosis towards the end of life can be difficult, there are models (eg, the TEACHH model)5 that can be useful in guiding clinicians in this process. Nonetheless, given the large body of evidence supporting the use of SFRT for bone metastases, there is a need to raise awareness of the recommendation to use of SFRT instead of MFRT, especially at the end of life, among radiation oncologists, other health professionals and patients. This can be achieved through health education initiatives such as the Choosing Wisely campaign (https://www.choosingwisely.org.au/).