Sök
User Profile
Change
Select your user profile

Elecsys® AFP

Immunoassay for the in vitro quantitative determination of α1‑fetoprotein in human serum and plasma.
Elecsys Reagent Pack

Immunoassay for the in vitro quantitative determination of α1‑fetoprotein in human serum and plasma.

Alpha1‑fetoprotein (AFP), an albumin‑like glycoprotein with a molecular weight of approximately 70 kDa, is formed in the yolk sac during fetal life, in non‑differentiated liver cells, and the fetal gastro‑intestinal tract.1,2

Tumors that synthesize AFP are mainly testicular non-seminomatous germ cell tumors (NSGCT), yolk sac tumors of the ovary and hepatocellular carcinoma (HCC). Moreover AFP is an important part in the risk assessment for trisomy 21 in the second trimester of pregnancy together with hCG+β and other parameters.3

The assay is inteded for the use as

  • An aid in the diagnosis of hepatocellular carcinoma (HCC).
  • An aid in the management of patients with non-seminomatous germ cell tumors.
  • One component in combination with other parameters to evaluate the risk of trisomy 21 (Down syndrome). Further testing is required for diagnosis of chromosomal aberrations.4,5

 

Testicular cancer

 

Careful monitoring of the serum tumor markers AFP and human chorionic gonadotropin (hCG) is essential in the management of patients with germ cell tumors (GCT), as these markers are important for diagnosis, as prognostic indicators, in monitoring treatment response, and in the detection of early relapse.6 In addition, hCG and AFP are important parameters for estimating the survival rate of patients with advanced NSGCTs and are also recommended by the National Academy of Clinical Biochemistry for the management of such patients.7

 

Hepatocellular carcinoma

 

Hepatocellular carcinoma (HCC) is frequently the result of advanced liver disease and can develop in patients with and without cirrhosis.8 AFP has long been recognized as a biomarker for HCC, and has played a prominent role in the diagnosis of HCC. Substantially elevated AFP values can indicate primary liver cell carcinoma and it has been shown that AFP levels increase with tumor size.9 Diagnosis of HCC has primarily relied on the presence of typical features seen on contrast-enhanced imaging studies, histopathological assessment, and serum AFP levels.10 While AFP is elevated during hepato‑carcinogenesis, it can also be found in other tumors such as testicular, embryonic or gastric cancer.11,12 AFP has reported sensitivities ranging from 39 to 65 %, and specificities from 76 to 94 % in HCC patients.13 The divergence in sensitivity and specificity of AFP in these studies is probably due to a variety of factors including different etiologies, variable study designs, and different cutoff values. As the AFP values can also rise during regeneration of the liver, moderately elevated values are found in alcohol‑mediated liver cirrhosis and acute viral hepatitis.14 Surveillance of patients at risk for developing HCC by abdominal ultrasonography in combination with AFP is recommended by several clinical practice guidelines.15,16, 17

 

Trisomy 21

 

Measurement of AFP makes a contribution to the risk assessment for trisomy 21 (Down syndrome) in the second trimester of pregnancy together with hCG+β and other parameters, such as exact gestational age and maternal weight.3 In a trisomy 21 affected pregnancy the maternal serum concentration of AFP is decreased whereas the maternal serum hCG+β concentration is approximately twice the normal median.18 The risk for a trisomy 21 affected pregnancy in the second trimester can be calculated by a suitable software (see “Materials required, but not provided” section6,7) using the algorithm as described by Cuckle et al.19 and the respective assay specific parameters.20,21,22,23,24

Related instruments

KONTAKTA OSS

Elecsys® AFP4,5

  • Systems

    cobas e 411 analyzer, cobas e 601 / cobas e 602 modules
    cobas e 801 analytical unit, cobas e 402 analytical unit

  • Testing Time

    18 minutes

  • Test principle

    Two-step double antigen sandwich assay

  • Calibration

    2-point

  • Sample material

    Serum collected using standard sampling tubes or tubes containing separating gel; Li-heparin, K2-EDTA and K3-EDTA plasma; Li-heparin plasma tubes containing separating gel

  • Sample volume

    10 μL cobas e 411 analyzer, cobas e 601 / cobas e 602 modules
    6 μL cobas e 801 analytical unit, cobas e 402 analytical unit

  • Onboard stability

    8 weeks on cobas e 411 analyzer and cobas e 601 module
    4 weeks on cobas e 602 module
    16 weeks on cobas e 801, cobas e 402 analytical units

  • Measuring range

    0.500 – 1,000 IU/mL (0.605 – 1,210 ng/mL) on cobas e 411 analyzer, cobas e 601 / cobas e 602 modules

    0.75 – 1000 IU/mL (0.908 – 1,210 ng/mL) on cobas e 801 analytical unit, cobas e 402 analytical unit

  • Limit of Detection (LoD)

    cobas e 411 analyzer, cobas e 601 / cobas e 602 modules: 0.50 IU/mL (0.61 ng/mL)
    cobas e 801 , cobas e 402 analytical units: 1.5 IU/mL

  • Limit of Quantitation (LoQ)

    cobas e 801, cobas e 402 analytical units: 2.25 IU/mL

  • Intermediate precision in positive samples*

    cobas e 411 analyzer: CV 2.4 – 3.1 %
    cobas e 601 / cobas e 602 modules: CV 2.6 – 3.8 %
    cobas e 801, cobas e 402 analytical units: CV 1.6 – 2.1 %

  • Repeatability in positive samples*

    cobas e 411 analyzer: CV 1.5 – 2.0 %
    cobas e 601 / cobas e 602 modules: CV 1.4 – 1.8 %
    cobas e 801, cobas e 402 analytical units: CV 1.0 – 1.4 %

* Human samples only

Related information

...
    ...

    References

    1. Taketa K. Alpha-Fetoprotein in the 1990s. In: Sell SS. Serological cancer markers. Humana Press 1992;31-46, ISBN: 0-89603-209-4
    2. Terentiev AA., Moldogazieva NT. Alpha-fetoprotein: a renaissance. Tumor Biology 2013;34:2075-2091.
    3. Wald NJ, Kennard A, Densem JW, et al. Antenatal maternal serum screening for Down’s syndrome: results of a demonstration project. BMJ 1992;305:391-394. 2020-11, V 5.0 English 5 / 6 Elecsys AFP 07026706500V5.0
    4. Elecsys® AFP Method Sheet for material 04481798190 v17 for cobas e 411, cobas e 601 & cobas e 602
    5. Elecsys® AFP Method Sheet for material 07026706190 v6 for cobas e 801 & cobas e 402
    6. Klepp O. Serum tumor markers in testicular and extragonadal germ cell malignancies. Scand J Clin Lab Invest Suppl 1991;206:28-41.
    7. Sturgeon CM, Duffy MJ, Stenman UH, et al. National Academy of Clinical Biochemistry Laboratory Medicine Practice Guidelines for Use of Tumor Markers in Testicular, Prostate, Colorectal, Breast, and Ovarian Cancers. Clin Chem 2008;54:12:e11-e79.
    8. Llovet JM, Zucman-Rossi J, Pikarsky E, et al. Hepatocellular carcinoma. Nature Reviews Disease Primers. 2016;14:2:16018.
    9. Toro A, Ardiri A, Mannino M, et al. Effect of pre- and post-treatment alpha-fetoprotein levels and tumor size on survival of patients with hepatocellular carcinoma treated by resection, transarterial chemoembolization or radiofrequency ablation: a retrospective study. BMC surgery 2014;14:40.
    10. Gonzalez SA and Keeffe EB. Diagnosis of Hepatocellular Carcinoma: Role of Tumor Markers and Liver Biopsy. Clin Liver Dis 2011;15:297-306.
    11. Gupta S, Bent S, Kohlwes J. Test characteristics of alpha-fetoprotein for detecting hepatocellular carcinoma in patients with hepatitis C. A systematic review and critical analysis. Ann. Intern. Med. 2003;139(1):46-50.
    12. Chen J, Röcken C, Treiber G, et al. Clinical implications of alphafetoprotein expression in gastric adenocarcinoma. Dig Dis 2003;21(4):357-362.
    13. Daniele B, Bencivenga A, Megna AS, et al. Alpha-fetoprotein and ultrasonography screening for hepatocellular carcinoma. Gastroenterology 2004;127:108-112.
    14. Stuart KE, Anand AJ, Jenkins RL. Hepatocellular Carcinoma in the United States. Prognostic features, treatment outcome, and survival. Cancer 1996;77,11:2217-2222.
    15. Singal A, et al. AASLD Practice Guidance on prevention, diagnosis, and treatment of hepatocellular carcinoma. Hepatology, 2023. | DOI: 10.1097/HEP.0000000000000466
    16. Kokudo N, Hasegawa K, Akahane M, et al. Evidence-based Clinical Practice Guidelines for Hepatocellular Carcinoma: The Japan Society of Hepatology 2013 update (3rd JSH-HCC Guidelines). Hepatol Res 2015; 45:123-127.
    17. Omata M, Cheng AL, Kokudo N, et al. Asia-Pacific clinical practice guidelines on the management of hepatocellular carcinoma: a 2017 update. Hepatol Int 2017;11:317-370.
    18. Schlebusch H. Prenatal screening for Down’s syndrome. In: Thomas L (ed.). Clinical Laboratory Diagnosis, TH-Books, Frankfurt, 1st English edition 1998:1124-1125.
    19. Cuckle HS, Wald NJ, Thompson SG. Estimating a woman’s risk of having a pregnancy associated with Down’s syndrome using her age and serum alpha-fetoprotein level. Br J Obstet Gynaecol 1987;94:387-402.
    20. Reynolds TM, Penney MD. The mathematical basis of multivariate risk screening: with special reference to screening for Down’s syndrome associated pregnancy. Ann Clin Biochem 1989;26:452-458.
    21. Cuckle HS, Wald NJ, Nanchahal K, et al. Repeat maternal serum alpha-fetoprotein testing in antenatal screening programmes for Down’s syndrome. Br J Obstet Gynaecol 1989;96:52-60.
    22. Dunstan FDJ, Gray JC, Nix ABJ, et al. Detection rates and false positive rates for Down’s Syndrome screening: How precisely can they be Estimated and what factors influence their value? Statistics Medicine 1997;16:1481-1495.
    23. Lamson SH, Hook B. Comparison of Mathematical Models for the Maternal Age Dependence of Down’s Syndrome Rates. Hum Genet Vol 1981;59:232-234.
    24. Cuckle HS. Improved parameters for risk estimation in Down’s syndrome screening. Prenat Diagn 1995;15:1057-1065.
    ...
      ...