THE BENEFIT AND COST OF PROSTATE-CANCER EARLY DETECTION

Cost-effectiveness calculations of prostate cancer early detection have not been possible due to the lack of any data demonstrating reduction in mortality from any test or procedure. Prior analyses focused only on cost assessments without consideration of any possible benefits. We used current data from three consecutive years of the American Cancer Society-National Prostate Cancer Detection Project to assess different economic perspectives of test performance, marginal costs, and benefit-cost analysis. The marginal cost, or cost per cancer, of digital rectal examination (DRE) markedly increased by the third year relative to several proposed prostate-specific antigen (PSA) scenarios. Sensitivity analysis for average cost showed that at 4 ng/ml, pricing PSA below $30 would be the most potent factor in potentially lowering costs. Analysis of receiver operator characteristic curves suggested that optimal performance for PSA may be at 3 ng/ml when combined with DRE or between 2 to 3 ng/ml when used alone. Benefit-cost calculations demonstrated that DRE when performed by highly skilled examiners had the lowest cost. However, DRE became one of the most costly detection scenarios when a minor decrease in performance was assumed. Sensitivity analysis demonstrated that the three most determinant parameters of net benefit, in decreasing order, are: specificity, benefits from earlier therapy, and prevalence. If a slightly more specific PSA assay is developed, the higher prevalence of clinically detectable prostate cancer could also make screening less costly than breast cancer screening. Under the assumptions of these analyses, the combination of PSA and DRE appears to represent an ethical and economical detection choice for individual patients in consultation with their physicians. Additional research is needed to quantify the significance of differences between different screening strategies.