Actual versus optimal radiotherapy utilisation for metastatic cancer patients in the 45 and Up Study Cohort, New South Wales

Aims: Radiotherapy can provide quality of life and/or survival benefits to patients with metastatic cancer on diagnosis (MCOD). However, little is known about radiotherapy utilisation in this population. We compared the optimal radiotherapy rates with actual uptake for people who present with MCOD in the 45 and Up Study cohort, and examined factors associated with utilisation. Materials and methods: In total, 267 153 individuals aged ≥45 enrolled in the Sax Institute's 45 and Up Study completed a baseline questionnaire during 2006–2009, providing sociodemographic and health information and consent for linkage to administrative health databases. Participants diagnosed up to December 2013 with MCOD were identified in the New South Wales Cancer Registry. Radiotherapy receipt was determined from claims to the Medicare Benefits Schedule and/or records in the New South Wales Admitted Patient Data Collection (2006 to June 2016). The Collaboration for Cancer Outcomes, Research and Evaluation optimal utilisation model was adapted for patients with MCOD to provide a benchmark. Results: Of 17 687 participants diagnosed with cancer after completion of the baseline questionnaire, 2392 had MCOD. Of patients with MCOD, 25% had primary lung cancer, which was the most common site. The actual radiotherapy utilisation rate for all patients was 32.3%, lower than the optimal of 45.0%. From multivariable analysis, patients who were aged ≥80 years and/or needed help with daily tasks and/or had a Charlson Comorbidity Index ≥2 were less likely to receive radiotherapy. Conclusions: Actual uptake of radiotherapy was below optimal. Elderly patients and/or those with more comorbidities were less likely to receive radiotherapy. These results suggest a potential role for advocacy and education around radiotherapy for these patient groups.