Study Type – Diagnostic (cost effectiveness) Level of Evidence 2b What's known on the subject? and What does the study add? The Beckman Coulter prostate health index ( phi ) was developed as a combination of serum prostate specific antigen (PSA), free PSA and a PSA precursor form [−2]proPSA to calculate the probability of prostate cancer and was used as an aid in distinguishing prostate cancer from benign prostatic conditions for men with PSA test 2–10 ng/mL and non‐suspicious digital rectal examination. Phi has been shown to improve diagnostic accuracy in prostate cancer detection compared with total and free PSA. An earlier 1‐year budget impact analysis revealed it to be a complementary approach to current prostate cancer screening strategies. The current study evaluated the cost‐effectiveness of early prostate cancer detection with phi in combination with a PSA test compared with a PSA test alone from the US societal perspective. The model with over 25 annual screening cycles for men aged 50–75 years indicated that PSA plus phi dominated the PSA test alone in prostate cancer detection and consequent treatment. PSA plus phi may be an important strategy for prostate cancer detection. OBJECTIVE To evaluate the cost‐effectiveness of early prostate cancer detection with the Beckman Coulter Prostate Health Index ( phi ) (not currently available in the USA) adding to the serum prostate‐specific antigen (PSA) test compared with the PSA test alone from the US societal perspective. PATIENTS AND METHODS Phi was developed as a combination of PSA, free PSA, and a PSA precursor form [−2]proPSA to calculate the probability of prostate cancer and was used as an aid in distinguishing prostate cancer from benign prostatic conditions for men with a borderline PSA test (e.g. PSA 2–10 ng/mL or 4–10 ng/mL) and non‐suspicious digital rectal examination. We constructed a Markov model with probabilistic sensitivity analysis to estimate expected costs and utilities of prostate cancer detection and consequent treatment for the annual prostate cancer screening in the male population aged 50–75 years old. The transition probabilities, health state utilities and prostate cancer treatment costs were derived from the published literature. The diagnostic performance of phi was obtained from a multi‐centre study. Diagnostic related costs were obtained from the 2009 Medicare Fee Schedule. Cost‐effectiveness was compared between the strategies of PSA test alone and PSA plus phi under two PSA thresholds (≥2 ng/mL and ≥4 ng/mL) to recommend a prostate biopsy. RESULTS Over 25 annual screening cycles, the strategy of PSA plus phi dominated the PSA‐only strategy using both thresholds of PSA ≥2 ng/mL and PSA ≥4 ng/mL, and was estimated to save $1199 or $443, with an expected gain of 0.08 or 0.03 quality adjusted life years, respectively. The probabilities of PSA plus phi being cost effective were approximately 77–70% or 78–71% at a range of $0–$200 000 willingness to pay using PSA thresholds ≥2 ng/mL and ≥4 ng/mL, respectively. CONCLUSION The strategy PSA plus phi may be an important strategy for prostate cancer detection at both thresholds of PSA ≥2 ng/mL and PSA ≥4 ng/mL to recommend a prostate biopsy compared with using PSA alone.
Deciding when to biopsy a man with non-suspicious DRE findings and tPSA in the 4–10 ng/ml range can be challenging, because two-thirds of such biopsies are typically found to be benign. The Prostate Health Index (phi) exhibits significantly improved diagnostic accuracy for prostate cancer detection when compared to tPSA and %fPSA, however only one published study to date has investigated its impact on biopsy decisions in clinical practice. An IRB approved observational study was conducted at four large urology group practices using a physician reported two-part questionnaire. Physician recommendations were recorded before and after receiving the phi test result. A historical control group was queried from each site's electronic medical records for eligible men who were seen by the same participating urologists prior to the implementation of the phi test in their practice. 506 men receiving a phi test were prospectively enrolled and 683 men were identified for the historical control group (without phi). Biopsy and pathological findings were also recorded for both groups. Men receiving a phi test showed a significant reduction in biopsy procedures performed when compared to the historical control group (36.4% vs. 60.3%, respectively, P < 0.0001). Based on questionnaire responses, the phi score impacted the physician's patient management plan in 73% of cases, including biopsy deferrals when the phi score was low, and decisions to perform biopsies when the phi score indicated an intermediate or high probability of prostate cancer (phi ≥36). phi testing significantly impacted the physician's biopsy decision for men with tPSA in the 4–10 ng/ml range and non-suspicious DRE findings. Appropriate utilization of phi resulted in a significant reduction in biopsy procedures performed compared to historical patients seen by the same participating urologists who would have met enrollment eligibility but did not receive a phi test.
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.
