Key Features and Values
- Same sample type can be used across all assays to simplify inclusion into routine serology work-up
- Ready to use reagents reduces hands-on time for assay preparation
- Long shelf life cost-effective solution by reducing wastage due to expired kit
- Suitable for inclusion on automated plate systems simplifies scale-up of test volume
- Supported by a complete panel of assays for supporting treatment monitoring of several forms of cancer
Free PSA ELISA is used for the quantitative determination of free Prostate Specific Antigen (f-PSA) in human serum or plasma samples. The determination of f-PSA levels is generally used in conjunction with a total PSA (t-PSA) measurement to determine the ratio between f-PSA and t-PSA. This ratio helps to estimate the risk for prostate cancer and to discriminate between elevated t-PSA levels caused by cancerous or non-cancerous conditions. F-PSA determinations are especially recommended for men with elevated t-PSA levels and negative results with digital rectal examination (DRE) in order to decide if a second prostate biopsy is indicated.
1. World Cancer Report. World Health Organisation. 2014. Chapter 5.11 ISBN 978-9283204299
2. Henttu P and Vihko P. Prostate-specific antigen and human glandular kallikrein: two kallikreins of the human prostate. Amm Med 1994, 26(3):157-64.
3. Balk SP, Ko YL and Bubley GJ. Biology of prostate specific antigen. J Clin Oncol. 2003, 15;21(2):383-91.
4. Zhou AM et al. Multiple forms of prostate-specific antigen in serum: differences in immunorecognition by monoclonal and polyclonal assays. Clin Chem. 1993, 39(12):2483-91.
5. Fritsche HA and Babalan RJ. Analytical performance goals for measuring prostate-specific antigen. Clin Chem, 1993, 39: 1529-1529.
6. Velonas VM, Woo HH, dos Remedios CG, Assinder SJ. Current status of biomarkers for prostate cancer. Int J Mol Sci. 2013, 24;14(6):11034-60.
7. Gion M et al. Percent free prostate-specific antigen in assessing the probability of prostate cancer under optimal analytical conditions. 1998, Clin Chem 44(12):2462-70.
8. Akdas et al. The role of free prostate specific antigen in the diagnosis of prostate cancer. British J Urol,1997, 79: 920-923.
9. Chen YT et al. Using proportions of free to total prostate-specific antigen, age and total prostate specific antigen to predict the probability of prostate cancer. Urology, 1996, 47(4):518-24.
10. Catalona et al. Use of the percentage of free prostate specific antigen to enhance differentiation of prostate cancer from benign prostatic disease: a prospective multicenter clinical trial. JAMA, 1998, 20;279(19):1542-7.
11. Liu J et al. Establishment of two new predictive models for prostate cancer to determine whether to require prostate biopsy when the PSA level is in the diagnostic gray zone (4-10 ng ml-1). Asian J Androl. 2019 21:1-4.
12. Huang Y, Li ZZ, Huang YL, Song HJ, Wang YJ. Value of free/total prostate-specific antigen (f/t PSA) ratios for prostate cancer detection in patients with total serum prostate-specific antigen between 4 and 10 ng/mL: A meta-analysis. Medicine (Baltimore). 2018; 97(13).
13. Duffy MJ. Biomarkers for prostate cancer: prostate specific antigen and beyond. Clin Chem Lab Med. 2019, 12. aop.
14. Carlsson SV and Roobol MJ. Improving the evaluation and diagnosis of clinically significant prostate cancer in 2017. Curr Op in Urol. 2017 27(3): 198–204.
15. Milford Ward A et al. Prostate specific antigen: biology, biochemistry and available commercial assays. Ann Clin Biochem, 2001, 38: 633-651.
16. Price CP et al., Pre-and post-analytical factors that may influence use of serum prostate specific antigen and its isoforms in a screening program for prostate cancer. Ann Clin Biochem, 2001, 38: 188-216.
17. Ferguson J et al. Continued provision of WHO International Standards for total and free PSA: Content and commutability of replacement preparations. Clin Biochem. 2019 71:58-66.