TY - JOUR
T1 - [-2]Proenzyme Prostate Specific Antigen is More Accurate Than Total and Free Prostate Specific Antigen in Differentiating Prostate Cancer From Benign Disease in a Prospective Prostate Cancer Screening Study
AU - Le, Brian V.
AU - Griffin, Christopher R.
AU - Loeb, Stacy
AU - Carvalhal, Gustavo F.
AU - Kan, Donghui
AU - Baumann, Nikola A.
AU - Catalona, William J.
N1 - Funding Information:
Supported by Beckman Coulter, the Urological Research Foundation, Prostate SPORE Grant P50 CA90386-05S2 , the Robert H. Lurie Comprehensive Cancer Grant P30 CA60553 and Zero–the Project to End Prostate Cancer (formerly the National Prostate Cancer Coalition) .
PY - 2010/4
Y1 - 2010/4
N2 - Purpose: Due to the limited specificity of prostate specific antigen for prostate cancer screening, there is an ongoing search for adjunctive biomarkers. Retrospective studies have suggested that an isoform of proenzyme prostate specific antigen called [-2]proenzyme prostate specific antigen may enhance the specificity of prostate specific antigen based screening. We examined the usefulness of this isoform in a prospective prostate cancer screening study. Materials and Methods: From a population of 2,034 men undergoing prostate cancer screening we examined the relationship between the measurement of the [-2]isoform of proenzyme prostate specific antigen (p2PSA) and prostate cancer detection. Specifically we compared the usefulness of total prostate specific antigen, the ratio of free-to-total prostate specific antigen, the ratio of p2PSA-to-free prostate specific antigen, and a formula combining prostate specific antigen, free prostate specific antigen and p2PSA (the Beckman Coulter prostate health index or phi®) to predict prostate cancer in men from the study undergoing prostate biopsy with a prostate specific antigen of 2.5 to 10 ng/ml and nonsuspicious digital rectal examination. Results: Despite similar total prostate specific antigen (p = 0.88), percent free prostate specific antigen (p = 0.02) and %p2PSA (p = 0.0006) distinguished between positive and negative biopsy results. On ROC analysis %p2PSA (AUC 0.76) outperformed prostate specific antigen (AUC 0.50) and percent free prostate specific antigen (AUC 0.68) for differentiating between prostate cancer and benign disease. Setting the sensitivity at 88.5%, p2PSA led to a substantial improvement in specificity as well as positive and negative predictive values. The Beckman Coulter prostate health index (AUC 0.77) had the best overall performance characteristics. Conclusions: This is the first prospective study to our knowledge to demonstrate that p2PSA provides improved discrimination between prostate cancer and benign disease in screened men with a prostate specific antigen of 2.5 to 10 ng/ml and a negative digital rectal examination.
AB - Purpose: Due to the limited specificity of prostate specific antigen for prostate cancer screening, there is an ongoing search for adjunctive biomarkers. Retrospective studies have suggested that an isoform of proenzyme prostate specific antigen called [-2]proenzyme prostate specific antigen may enhance the specificity of prostate specific antigen based screening. We examined the usefulness of this isoform in a prospective prostate cancer screening study. Materials and Methods: From a population of 2,034 men undergoing prostate cancer screening we examined the relationship between the measurement of the [-2]isoform of proenzyme prostate specific antigen (p2PSA) and prostate cancer detection. Specifically we compared the usefulness of total prostate specific antigen, the ratio of free-to-total prostate specific antigen, the ratio of p2PSA-to-free prostate specific antigen, and a formula combining prostate specific antigen, free prostate specific antigen and p2PSA (the Beckman Coulter prostate health index or phi®) to predict prostate cancer in men from the study undergoing prostate biopsy with a prostate specific antigen of 2.5 to 10 ng/ml and nonsuspicious digital rectal examination. Results: Despite similar total prostate specific antigen (p = 0.88), percent free prostate specific antigen (p = 0.02) and %p2PSA (p = 0.0006) distinguished between positive and negative biopsy results. On ROC analysis %p2PSA (AUC 0.76) outperformed prostate specific antigen (AUC 0.50) and percent free prostate specific antigen (AUC 0.68) for differentiating between prostate cancer and benign disease. Setting the sensitivity at 88.5%, p2PSA led to a substantial improvement in specificity as well as positive and negative predictive values. The Beckman Coulter prostate health index (AUC 0.77) had the best overall performance characteristics. Conclusions: This is the first prospective study to our knowledge to demonstrate that p2PSA provides improved discrimination between prostate cancer and benign disease in screened men with a prostate specific antigen of 2.5 to 10 ng/ml and a negative digital rectal examination.
KW - early detection of cancer
KW - prostate-specific antigen
KW - protein isoforms
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U2 - 10.1016/j.juro.2009.12.056
DO - 10.1016/j.juro.2009.12.056
M3 - Article
C2 - 20171670
AN - SCOPUS:77949277570
SN - 0022-5347
VL - 183
SP - 1355
EP - 1359
JO - Journal of Urology
JF - Journal of Urology
IS - 4
ER -
