MP6-04 THE 4KSCORE TEST PREDICTS HIGH-GRADE PROSTATE CANCER ON BIOPSY WITH PSA LESS THAN 4 NG PER MILLILITER

Abstract

You have accessJournal of UrologyProstate Cancer: Markers II1 Apr 2015MP6-04 THE 4KSCORE TEST PREDICTS HIGH-GRADE PROSTATE CANCER ON BIOPSY WITH PSA LESS THAN 4 NG PER MILLILITER Vinita Mathur, Vincent Linder, Yan Dong, Dan Sjoberg, Richard Roberts, Michael Reeve, David Okrongly, Jay Newmark, Grannum Sant, and Mitchell Steiner Vinita MathurVinita Mathur More articles by this author , Vincent LinderVincent Linder More articles by this author , Yan DongYan Dong More articles by this author , Dan SjobergDan Sjoberg More articles by this author , Richard RobertsRichard Roberts More articles by this author , Michael ReeveMichael Reeve More articles by this author , David OkronglyDavid Okrongly More articles by this author , Jay NewmarkJay Newmark More articles by this author , Grannum SantGrannum Sant More articles by this author , and Mitchell SteinerMitchell Steiner More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2015.02.251AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES PSA values below 4ng/mL are considered “normal”, however studies have shown that up to 15% of men in the general population with these low levels will have prostate cancer on biopsy of which 2% may be high grade (Gleason score 7 or higher). The 4Kscore test utilizes 4 kallikrein biomarkers; total PSA, free PSA, intact PSA, and human kallikrein2 in addition to digital rectal exam (DRE) and previous biopsy status to access risk of high grade prostate cancer. While the 4Kscore test has previously been shown to accurately predict the risk of high grade prostate cancer, we focused on patients with low/normal concentrations of PSA and assessed the ability of the 4Kscore test to predict the risk of high grade prostate cancer. METHODS Three hundred and forty eight men with PSA levels less than or equal to 4 ng/mL were identified in a recent large prospective study enrolling 1,012 men who were previously scheduled for prostate biopsy for suspicion of prostate cancer from 26 sites across the United States. The 4Kscore was calculated and subsequent biopsy results were retrieved. We investigated whether the 4Kscore test was predicative of risk of high grade cancer at “normal” PSA values. We evaluated the accuracy of the 4Kscore as a predictive model for patients with low tPSA by fitting a logistic regression model with high grade prostate cancer as the outcome. RESULTS Of the 348 men identified in our prospective clinical validation study of 1012 men with PSA values less than 4 ng/ml, 37 were diagnosed with high grade prostate cancer (11%) on biopsy. In this subgroup, the associated 4Kscore result was elevated in 35 of 37 patients (95%). CONCLUSIONS A normal PSA level (i.e. < 4 ng/ml) does not definitively rule out high grade prostate cancer. We have shown that the 4Kscore test performs consistently well as predictive instrument, even in the lower zone of tPSA <4 ng/mL. The 4Kscore test maintains good discrimination for risk of high grade prostate cancer in this subpopulation with a sensitivity of 95% and specificity of 56%. 4Kscore for Gleason Score ≤7 at total PSA values < 4ng/ml 4Kscore for Gleason ≤7 All patients Data Set N=348 N=1012 tPSA < 4ng/mL, Median 2.8ng/mL 0.2 to > 100ng/mL, Median 4.7 Gleason Score 37 (11%) 231 (23%) HG cases with increased 4Kscore∗ 35 (10%) 218 (22%) Sensitivity of 4Kscore test∗ 0.95 0.94 Specificity of 4Kscore test∗ 0.56 0.38 4Kscore for with Gleason Score ≤7 Mean 4Kscore value 22 Mean 4Kscore value 42 < 5% 2 (5%) 12 (5%) 5-10% 5 (14%) 13 (6%) 10-15% 9 (24%) 23 (10%) > 15 21 (57%) 183 (79%) AUC 0.858 (95% CI 0.799-0.908) 0.821 (95% CI 0.790-0.852) ∗ 4Kscore ≥6% © 2015 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 193Issue 4SApril 2015Page: e55 Advertisement Copyright & Permissions© 2015 by American Urological Association Education and Research, Inc.MetricsAuthor Information Vinita Mathur More articles by this author Vincent Linder More articles by this author Yan Dong More articles by this author Dan Sjoberg More articles by this author Richard Roberts More articles by this author Michael Reeve More articles by this author David Okrongly More articles by this author Jay Newmark More articles by this author Grannum Sant More articles by this author Mitchell Steiner More articles by this author Expand All Advertisement Advertisement PDF DownloadLoading ...