BackgroundIndividual behaviours are associated with prostate cancer (PC) progression. Behavioural scores, comprised of multiple risk factors, allow assessment of the combined impact of multiple behaviours.MethodsWe examined the association between six a priori scores and risk of PC progression and mortality among 2156 men with PC in the Cancer of the Prostate Strategic Urologic Research Endeavor (CaPSURE) cohort: two scores developed based on the PC survivorship literature (‘2021 Score [+ Diet]’); a score developed based on pre-diagnostic PC literature (‘2015 Score’); and three scores based on US recommendations for cancer prevention (‘WCRF/AICR Score’) and survival (‘ACS Score [+ Alcohol]’). Hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated for progression and PC mortality via parametric survival models (interval censoring) and Cox models, respectively.ResultsOver a median (IQR) of 6.4 (1.3, 13.7) years, we observed 192 progression and 73 PC mortality events. Higher (i.e., healthier) 2021 Score + Diet and WCRF/AICR Scores were inversely associated with risk of PC progression (2021 + Diet: HRcontinuous= 0.76, 95% CI: 0.63–0.90. WCRF/AICR: HRcontinuous= 0.83, 95% CI: 0.67–1.02) and mortality (2021 + Diet: HRcontinuous= 0.65, 95% CI: 0.45–0.93. WCRF/AICR: HRcontinuous= 0.71; 95% CI: 0.57–0.89). The ACS Score + Alcohol was only associated with progression (HRcontinuous= 0.89, 95% CI: 0.81–0.98) while the 2021 Score was only associated with PC mortality (HRcontinuous= 0.62, 95% CI: 0.45–0.85). The 2015 was not associated with PC progression or mortality.ConclusionFindings strengthen the evidence that behavioural modifications following a prostate cancer diagnosis may improve clinical outcomes.