Cost-effectiveness of percent free PSA for prostate cancer detection in men with a total PSA of 4-10 ng/ml.

OBJECTIVE To assess the cost-effectiveness of two diagnostic strategies for prostate cancer in men with prostate-specific antigen (PSA) levels of 4-10 ng/ml and normal digital rectal examination (DRE). DESIGN Cost-effectiveness analysis was performed using a decision tree model. Data collection and a systematic review of patients at the Urology Department (Carlos Haya Hospital) were made. 101 patients over the age of 40 with PSA levels of 4-10 ng/ml and normal DRE were selected. Transrectal ultrasound-guided prostate biopsy (TRUS-Bx) and percent free PSA testing prior to TRUS-Bx were performed. The outcome measures used were the incremental cost-effectiveness ratio, and costs were calculated through activity-based costing. The effectiveness was measured by means of the number of detected cases, test utility and actual cases (detected cases minus lost cases). RESULTS Using base-case analysis, the strategy of percent free PSA + TRUS-Bx was found to be the most cost-effective. The incremental cost-effectiveness ratio for free PSA + TRUS-Bx compared with TRUS-Bx was EUR 2,277.40. Strategy 2 (TRUS-Bx) would be more cost-effective if the cost of percent free PSA increased to EUR 21.64 or if prostate cancer prevalence increased to 26%. CONCLUSIONS The use of percent free PSA prior to TRUS-Bx is the most cost-effective diagnostic strategy. However, this result is very sensitive and strategy 2 (TRUS-Bx) would be more cost-effective if the cost of the percent free PSA increased to EUR 21.64 or if the prevalence of prostate cancer increased to above 26%.