108 COMPARISON OF CONVENTIONAL PSA AND NANOTECHNOLOGY PSA IN INDIVIDUAL PROSTATE CANCER PATIENTS (2010)

You have accessJournal of UrologyProstate Cancer: Basic Research I1 Apr 2010108 COMPARISON OF CONVENTIONAL PSA AND NANOTECHNOLOGY PSA IN INDIVIDUAL PROSTATE CANCER PATIENTS Hannah Alphs, Daniel C. O'Brien, Donghui Kan, Brian V. Le, Dae Y. Kim, Lee C. Zhao, Stacy Loeb, Norm D. Smith, Chad A. Mirkin, C. Shad Thaxton, Phillip R. Cooper, and William J. Catalona Hannah AlphsHannah Alphs Chicago, IL More articles by this author , Daniel C. O'BrienDaniel C. O'Brien Chicago, IL More articles by this author , Donghui KanDonghui Kan Chicago, IL More articles by this author , Brian V. LeBrian V. Le Chicago, IL More articles by this author , Dae Y. KimDae Y. Kim Chicago, IL More articles by this author , Lee C. ZhaoLee C. Zhao Chicago, IL More articles by this author , Stacy LoebStacy Loeb Baltimore, MD More articles by this author , Norm D. SmithNorm D. Smith Chicago, IL More articles by this author , Chad A. MirkinChad A. Mirkin Evanston, IL More articles by this author , C. Shad ThaxtonC. Shad Thaxton Chicago, IL More articles by this author , Phillip R. CooperPhillip R. Cooper Chicago, IL More articles by this author , and William J. CatalonaWilliam J. Catalona Chicago, IL More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2010.02.157AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES Commercial PSA assays are well-suited to prostate cancer screening. However, following radical prostatectomy (RP) patients frequently have serum PSA concentrations below those detectable by commercial immunoassays. Nanotechnology-based assays recently have been designed with greater sensitivity for detecting PSA post-RP. The objective of this study was to determine the extent to which nanotechnology PSA (nPSA) results correlate with conventional results. METHODS We tested 134 post-RP serum samples from patients with PSA concentrations <0.1 ng/mL (<100 pg/mL) measured in the Beckman-Coulter Access PSA immunoassay® and the Nanosphere research-use-only PSA assay®. We then determined the correlation between the two assays in the following conventional PSA (cPSA) ranges: 0.0, 0.01-0.03, 0.04-0.09 ng/mL. The first concentration point was chosen to correlate nPSA results with those beneath the limit of cPSA resolution. The second corresponds to the first tertile of detectable cPSA concentrations, and the final range represents the other two tertiles which were merged due to the small sample size (Note: In routine clinical practice, the Access PSA assay does not report PSA value to 2 decimal places). RESULTS Among 55 men with a cPSA assay result of 0.0 ng/mL following RP, the mean nPSA was 2.6 pg/mL (range 0.6 to 7.7). In men with cPSA levels of 0.01 to 0.03 ng/mL, the mean nPSA concentration was 9.4 pg/mL (range, 6 to 35), with a correlation coefficient of 0.678 (p<0.0001). Among patients with cPSA measurements of 0.04 to 0.09 ng/mL, the mean nPSA was 23.4 pg/mL (range 36 to 99). In the last subgroup, the cPSA and nPSA results had an inverse correlation of -0.219. The correlation coefficient determined for the entire group was 0.62 (p<0.0001). CONCLUSIONS In post-RP prostate cancer patients, PSA concentrations measured in the Beckman Coulter Access assay and the Nanosphere research-use-only PSA assay were well-correlated. Correlations were strongest at lower PSA concentrations. These results suggest that the nanotechnology and conventional PSA assays are similarly calibrated. Further study is warranted to determine the full clinical utility of the nPSA assay in the post-RP setting. Variable N Mean Med. Min Max Correlation 0.0 ng 55 Nano (pg/ml) 2.55 2.0 0.6 7.7 n/a Conv (ng/ml) 0 0 0 0 0.01-0.03 68 Nano (pg/ml) 9.43 6.2 0.5 44.7 0.678 Conv (ng/ml) .015 .01 .01 .03 P=<.0001 0.04-0.09 11 Nano (pg/ml) 23.37 20.2 1.4 57.5 -0.219 Conv (ng/ml) .062 .06 .04 .09 P=0.52 Total population correlation coefficient is 0.62, P=<0.0001 © 2010 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 183Issue 4SApril 2010Page: e44 Advertisement Copyright & Permissions© 2010 by American Urological Association Education and Research, Inc.MetricsAuthor Information Hannah Alphs Chicago, IL More articles by this author Daniel C. O'Brien Chicago, IL More articles by this author Donghui Kan Chicago, IL More articles by this author Brian V. Le Chicago, IL More articles by this author Dae Y. Kim Chicago, IL More articles by this author Lee C. Zhao Chicago, IL More articles by this author Stacy Loeb Baltimore, MD More articles by this author Norm D. Smith Chicago, IL More articles by this author Chad A. Mirkin Evanston, IL More articles by this author C. Shad Thaxton Chicago, IL More articles by this author Phillip R. Cooper Chicago, IL More articles by this author William J. Catalona Chicago, IL More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...