Background
Evidence-based modelling estimates show that 52% of prostate cancer patients would benefit from radiotherapy at diagnosis1-3. It was estimated that 5-year overall survival (OS) and local control (LC) shortfall due to not receiving RT were 1.1% and 12.4%4,5, respectively.
Aims: to calculate actual RT utilization rate, estimate shortfall in OS and irreplaceable LC and identify factors affecting RTU.
Methods
NSWCCR data for prostate cancer patients diagnosed from 2009-2011 were linked to radiotherapy, admitted patients, clinical cancer registry and death datasets. Patients located near State border where their closest RT facility was outside NSW (cross borders) were excluded from the analysis. Irreplaceable benefit of RT counted only where there was no guideline-recommended alternative treatment5.
Results
There were 19,816 prostate cancer patients during study period. Median age was 67 years, 65% had localized disease, 4% had distant disease and 30% had unknown stage. Of patients with localized disease, 18% received RT, 37% had radical prostatectomy (RP) and 4% had both RP and RT. 28% of patients had RP alone, 3% had RP & RT, 20% had RT alone and 49% had neither RP nor RT. Overall, 23% of all prostate cancer patients received RT within 1-year of diagnosis. OS and irreplaceable LC person-shortfall were 124 and 1398. Univariate and multivariate analysis showed that younger patients with loco-regional disease, living in least-disadvantaged areas and living >100km of RT facility were predictors for RT underutilization. Patients living in least-disadvantaged areas were 33% more likely to have RP than patients living in most-disadvantaged areas.
Implications
Prostate cancer constituted to 18% of patients diagnosed with cancer during study period. Underutilization of RT increases disease burden on health system due higher risks of local failure and OS shortfall. Giving RT according to evidence-based guidelines would probably have prevented 41 early deaths and 466 local failures annually.