Radiotherapy underutilisation and its impact on local control and survival in New South Wales, Australia.

Background And Purpose: This study aimed to identify the actual radiotherapy utilisation rate (A-RUR) in New South Wales (NSW) Australia for 2009-2011 and compare that to the published evidence-based optimal radiotherapy utilisation rate (O-RUR) and to previously reported A-RUR in NSW in 2004-2006. It also aimed to estimate the effect of underutilisation on 5-year local control (LC) and overall survival (OS) and identify factors that predict for underutilisation.

Materials And Methods: All cases of registered cancer diagnosed in NSW between 2009 and 2011 were identified from the NSW Central Cancer Registry and linked with data from all radiotherapy departments. The A-RUR was calculated and compared with O-RURs for all cancers. The difference for each indication was used to estimate 5-year OS and LC shortfall. Univariate and multivariate analyses were performed to identify factors that correlated with reduced radiotherapy utilisation.

Results: 110,645 cancer cases were identified. 25% received radiotherapy within one year of diagnosis compared to an estimated optimal rate of 45%. This has marginally improved from previously reported rate of 22% in NSW in 2004-2006. We estimated that 5-year OS and LC were compromised in 1162 and 5062 patients respectively. Factors that predicted for underuse of radiotherapy were older age, male gender, lower socioeconomic status, increasing distance to nearest radiotherapy centre and localised disease.

Conclusion: The identified deficit in radiotherapy use has a significant negative impact on patient outcomes. Strategies to overcome such shortfalls need to be developed to improve radiotherapy use and patient outcomes.