Abstract
Objective: The prostate health index (phi) has been shown to improve diagnostic accuracy in prostate cancer (Pca) detection compared with total and free serum prostate-specific antigen (PSA). The study assessed the cost-effectiveness of early Pca detection with phi plus PSA, compared with the PSA test alone, from a managed care organization perspective.
Study Design: Cost-effectiveness analysis.
Methods: A Markov model estimated expected costs and utilities of Pca detection and consequent treatment using four strategies in men aged 50-75 years. The strategies differed with the PSA test thresholds (≥2 or ≥4 ng/mL) and methods (PSA alone vs. PSA plus phi) to determine need for a prostate biopsy. The transition probabilities were derived from the electronic medical records of males in Kaiser Permanente Southern California during 1998-2007. Health state utilities and prostate cancer-related treatment costs were obtained from the published literature.
Results: The most cost-effective strategy used the PSA plus phi at PSA 2-10 ng/mL to determine need for a prostate biopsy, which had the lowest cost and highest effectiveness [cost/effectiveness (C/E)=13,650/15.491, $1,099/QALY]. Next was PSA plus phi at PSA 4-10 ng/mL [C/E=14,095/12.364, $1,140/QALY), followed by PSA test at threshold ≥4 ng/mL [C/E=15,256/12.304, $1,240/QALY), or PSA ≥2 ng/mL [C/E=15,789/12.287, $1,285/QALY). PSA plus phi at PSA 2-10 ng/mL displayed a 74% to 86% probability of being cost-effective at a willingness-to-pay range of 0 to $150,000/QALY gained.
Conclusions: Using the strategy PSA plus phi at PSA 2-10 ng/mL for Pca detection dominated other strategies, and was an optimal strategy under a willingness-to-pay of $150,000/QALY gained.