PSA testing in Austria: induced morbidity and saved mortality

Abstract

Opportunistic screening of healthy men by prostate-specific antigen (PSA) testing led to a steep increase of prostate cancer incidence in Austria. The objective of this study was to quantify how many additional men are diagnosed with prostate cancer by PSA testing, to save one man from prostate cancer death. Regression models for incidence and mortality for the time periods 1983-1991 and 1992-2003 by age groups 50-59 and 60-69 years were estimated. For 1992-2003, expected numbers of incidence and mortality were calculated. The first estimates for the years 1992-2003 were calculated using the regression model including the years 1983-1991. The second estimates were also calculated using the regression model, but including only the years 1992-2003. The difference between estimates was then summed up for 1992-2003. The corresponding sums of incidence and mortality were compared to provide estimates for the effect of the introduction of PSA screening on incidence/mortality ratio. According to our calculation for the time period 1992-2003, in age group 50-69 years, a total of 512 expected prostate cancer deaths were prevented because of opportunistic PSA screening, whereas PSA testing identified a total of 9648 additional men with asymptomatic prostate cancer. In conclusion, to save one man in the age group 50-69 years in the time period 1992-2003 from prostate cancer death by PSA testing, a total of 18.8 men with asymptomatic prostate cancer had to be identified. Although this study probably underestimates the benefit (reduced mortality) and overestimates excess incidence of prostate cancer, it is far from sure that in all of these additionally identified men prostate cancer would ever have surfaced as a clinical disease, if not screened for.