Description: Publication date: Available online 5 July 2018 Source: Radiotherapy and Oncology Author(s): Vikneswary Batumalai, Jesmin Shafiq, Gabriel Gabriel, Timothy P. Hanna, Geoff P. Delaney, Michael Barton Background and purpose Despite evidence of the benefits of radiotherapy (RT) in the treatment of cancer patients, its underutilisation has been reported for various tumour sites. The aim of this study was to estimate survival shortfall, ‘years of potential life lost’ (YPLL) and ‘disability-adjusted life years lost’ (DALY) to demonstrate the impact of radiotherapy underutilisation in Australia. Materials and methods Optimal and actual RT utilisation (RTU) was compared to assess RT underutilisation to estimate 5-year overall survival shortfall using 2006 data from New South Wales (NSW) for 26 common tumour sites. 5-year overall survival shortfall is defined as number of people not surviving for 5-years due to RT underutilisation [=benefit proportion × shortfall [(optimal-actual RTU)/optimal RTU] proportion × No. of new cases]. YPLL = survival shortfall × estimated years of life lost per person (overall life expectancy − median age at death for specific cancer). DALY = (Years lived with disability + Years of life lost) × survival shortfall. Results The total number of new cases with cancer in 2006 in NSW was 20,741. Optimal RTU was 48% while actual RTU was 26%, resulting in estimated of 411 deaths due to underutilisation. Each death resulted in an average of 10.4 YPLL and 17.5 DALY. It was estimated RT underutilisation resulted in a total of 4,289 YPLL and 7,192 DALY overall. Conclusion This study illustrates the value of considering different mortality statistics, which include measures of the burden of cancer deaths on both the population and patients.