Elecsys® total PSA and free PSA

  • Prostate cancer is the second most common cancer in men1a and the leading death cause from cancer in men.1b
  • Early detection ensures timely management and treatement before prostate cancer can cause potentially fatal conditions.2
  • Screening approaches have reduced prostate cancer mortality in the USA and in Europe.3,4,5 Most international guidelines recommend informed decision making regarding PSA testing.6,7
  • Measuring total PSA in conjunction with DRE serves as an aid in diagnosis of prostate cancer.
  • For patients with total PSA values between 4 – 10 ng/mL, measuring free PSA and calculating the free-to-total PSA ratio can help determining the need for a biopsy.8,9
  • Total PSA can also be used to assess therapy response and for recurrence monitoring10

Elecsys total PSA
 

Assay time 18 min
Traceability Standardized against the Stanford Reference Standard/WHO 96/670
(90 % PSA-ACT + 10 % free PSA)
Sample material Serum, Li-heparin, K3-EDTA and sodium citrate plasma.
When sodium citrate is used, the results must be corrected by +10%
Sample volume 20 μL
Detection Limit 0.002 ng/mL (Elecsys® 2010 and cobas e 411 analyzer) 0.003 ng/mL (E 170 and cobas e 601, e 602 modules)
Measuring Range 0.002 – 100 ng/mL (Elecsys® 2010 and cobas e 411 analyzer) 0.003 – 100 ng/mL (E 170 and cobas e 601, e 602 modules)

 

 

Elecsys free PSA
 

Assay time 18 min
Traceability Standardized against the Stanford Reference Standard/WHO 96/668
(100 % free PSA)
Sample material Serum, Li-heparin, K3-EDTA and sodium citrate plasma.
When sodium citrate is used, the results must be corrected by +10%.
Sample volume 20 μL
Detection Limit ≤ 0.01 ng/mL
Measuring Range 0.01 – 50 ng/mL

Elevated total PSA value can aid in the diagnosis of prostate cancer

  • Serum PSA values increase with age. Reference values for specific age groups have been determined8
Age (years) Number of Patients Total PSA (ng/mL) 95th percentile
<40 45 1.4
40-49 42 2.0
50-59 107 3.1
60-69 41 4.1
≥ 70 9 4.4
  • Elevated total PSA values in men aged 50 or older can indicate a higher probability of finding cancer at biopsy

%free PSA serves as a second line test to determine the probability of detecting cancer at biopsy

  • In men aged 50, or older, with a negative DRE and a total PSA value of 4-10 ng/ml, %free PSA can be measured to assess the need for a prostate biopsy9
  • In these patients, the probability of finding prostate cancer is higher when %free PSA is low

Serial measurements of total PSA are indicated as a post-treatment follow-up measure

  • Increasing total PSA values after treatment can indicate recurrence
  • The 2014 NCCN guidelines recommend to test PSA every 6 – 12 months during 5 years following radiation therapy or radical prostatectomy10

The performance of Elecsys total PSA is highly reliable for the monitoring of prostate cancer patients

  • With a lower detection limit (LDL) of 0.003 ng/mL, Elecsys total PSA is able to detect early elevations of PSA8
  • With a proven excellent lot-to-lot consistency, Elecsys total PSA is well suited for prostate cancer monitoring

Monitoring recovery of Elecsys PSA

1a www.cancer.org/cancer/prostatecancer/detailedguide/prostate-cancer-key-statistics accessed on Aug. 6th 2015
1b Globocan 2012
2 Esserman, L., Shieh, Y. & Thompson, I. Rethinking screening for breast cancer and prostate cancer. JAMA 302, 1685–1692 (2009).
3 Siegel, R., Naishadham, D. & Jemal, A. Cancer statistics, 2012. CA Cancer J. Clin. 62, 10–29 (2012).
4 Schröder, M.D. et al; N Engl J Med 2009;360:1320–8.
5 Bray, F., Lortet-Tieulent, J., Ferlay, J., Forman, D. & Auvinen, A. Prostate cancer incidence and mortality trends in 37 European countries: an overview. Eur. J. Cancer 46, 3040–3052 (2010).
6 Early detection of Prostate Cancer: AUA Guidelines 2013
7 European Association of Urology: Guidelines on Prostate Cancer
8 Elecsys total PSA package insert.
9 Elecsys free PSA package insert.
10 NCCN guidelines on prostate cancer 2014.
11 Result from the multicenter evaluation. Data on file at Roche
12 Roobol, M. J. & Carlsson, S. V. Nat. Rev. Urol. 10, 38–48 (2013); published online 18 December 2012.
13 Shariat, S. F., Kattan, M. W., Vickers, A. J., Karakiewicz, P. I. & Scardino, P. T. Critical review of prostate cancer predictive tools. Future Oncol. 5, 1555–1584 (2009).
14 Schroeder, F. & Kattan, M. W. The comparability of models for predicting the risk of a positive prostate biopsy with prostate-specific antigen alone: a systematic review. Eur. Urol. 54, 274–290 (2008).
15 Shariat, S. F., Karakiewicz, P. I., Suardi, N. & Kattan, M. W. Comparison of nomograms with other methods for predicting outcomes in prostate cancer: a critical analysis of the literature. Clin. Cancer Res. 14, 4400–4407 (2008).
16 Dall’Era M.A., et al. European Urology 62 (2012) 976–983.
17 Donovan, J. L. J Natl Cancer Inst Monogr(2012) 2012 (45):191–196.
18 Lane J.A., et al, Lancet Oncol. 2014 Sep;15(10):1109–18.