a Division of OPKO Health, Inc.

© 2014 OPKO All rights reserved

The Challenge of Prostate Biopsy Decision Making

The Need for Improved Diagnostic Information

•   Provide information to improve decision making before having a prostate biopsy

•   Reduce the number of unnecessary biopsies, associated complications, and costs

•   Provide diagnostic information from a blood test; no requirement for biopsy tissue

•   Demonstrate a potential for a significant health economic benefit

The OPKO 4Kscore Test - Adding Clarity to Shared Decision Making

Elements of the 4Kscore Test

The 4Kscore Test relies on the measurement of four prostate-specific kallikreins in blood: Total PSA, Free PSA, Intact PSA, Human Kallikrein 2 (hK2). The blood test results are combined in an algorithm with patient age, DRE (nodules, no nodules), prior negative biopsy (yes/no). The result is a patient specific probability for finding a high-grade, Gleason score 7 or higher prostate cancer upon biopsy. (Low Risk patient example at right)

4Kscore Test: Rigorous Clinical Development

The 4Kscore test was developed by OPKO Lab and is performed by OPKO Lab at its CLIA-accredited laboratory facility. The biomarkers utilized in the 4Kscore Test are based on over a decade of research conducted by scientists at Memorial Sloan Kettering Cancer Center and leading research centers in Europe on over 10,000 patients. 1-8 The results have recently been replicated in a prospective blinded clinical study conducted at 26 urology centers in the United States on over 663 patients. 9 A recent health economic analysis demonstrated that use of the 4Kscore Test could result in annual savings approaching $1 billion in the US. 10

Data from the US Clinical Study

Clinical Study Design

A total of 663 patients were enrolled from October 2013 to March 2014 in a blinded, prospective clinical study at 26 Urology centers in the US to validate the performance of the 4Kscore Test. In order to obtain a cohort representative of current biopsy selection practice, enrollment was open to all men scheduled for a prostate biopsy, regardless of age, PSA, DRE, or prior biopsy. Each participant underwent a TRUS prostate biopsy of at least 10 cores, and histopathology was conducted according to the established practice at each center. Patients with a treatment history known to influence PSA levels were excluded. A blinded blood sample (K2EDTA) was collected prior to the biopsy and sent to OPKO Lab, Nashville, TN for the four kallikrein testing (Total PSA, Free PSA, Intact PSA and hK2). The four kallikrein results, histopathology, age, DRE, and prior biopsy data were unblinded and analyzed by independent biostatisticians.

1 Vickers, AJ et al. A panel of kallikrein markers can reduce unnecessary biopsy for prostate cancer: data from the European Randomized Study of Prostate Cancer Screening in Goteborg, Sweden. BMC Medicine, 2008, 6, 19.
2 Vickers, AJ et al. Impact of recent screening on predicting the outcome of prostate cancer biopsy in men with elevated prostate-specific antigen: data from the European Randomized Study of Prostate Cancer Screening in Gothenburg, Sweden. Cancer. 2010, 116, 2612.
3 Vickers, AJ et al. Reducing unnecessary biopsy during prostate cancer screening using a four-kallikrein panel: an independent replication. J Clin Oncol. 2010, 28, 2493.
4 Vickers, AJ et al. A four-kallikrein panel predicts prostate cancer in men with recent screening: data from the European Randomized Study of Screening for Prostate Cancer, Rotterdam. Clin Cancer Res. 2010, 16, 3232.
5 Gupta, A et al. A four-kallikrein panel for the prediction of repeat prostate biopsy: data from the European Randomized Study of Prostate Cancer screening in Rotterdam, Netherlands. Br J Cancer. 2010, 103, 708.
6 Benchikh, A et al. A panel of kallikrein markers can predict outcome of prostate biopsy following clinical work-up: an independent validation study from the European Randomized Study of Prostate Cancer screening, France. BMC Cancer. 2010, 10, 635.
7 Vickers, AJ et al. A panel of kallikrein marker predicts prostate cancer in a large, population-based cohort followed for 15 years without screening. Cancer Epidemiol Biomarkers Prev. 2011, 20, 255.
8 Carlsson, S et al. Predictive value of four kallikrein markers for pathologically insignificant compared with aggressive prostate cancer in radical prostatectomy specimens: results from the European Randomized Study of Screening for Prostate Cancer section Rotterdam. Eur Urol. 2013, 64,693.
9 Lin, DW et al. Abstract accepted for Plenary Presentation at American Urological Association Annual Meeting, Orlando, FL, May 18, 2014.
10 Voigt, JD et al. The Kallikrein Panel for Prostate Cancer Screening: Its Economic Impact. Prostate. 2014, 74, 250.

•   PSA testing alone leads to a high number of negative biopsies or biopsies that detect only low-grade cancer

•   The controversy over PSA screening has resulted in less testing and perhaps a missed opportunity to continue
     the decline in prostate cancer mortality rates

•   The side effects of prostate biopsy (pain, bleeding, infection) make many men reluctant to have the procedure

•   Other patient factors including family history and co-morbidities further complicate the decision for a prostate 

To learn more, call:
1 (877) 922-8364

To learn more, call: 1 (877) 922-8364