Test Code LAB0232793 Beta-Human Chorionic Gonadotropin, Quantitative, Serum
Additional Codes
Mayo Test ID |
---|
BHCG |
Performing Laboratory
Mayo Clinic Laboratories in RochesterUseful For
Monitoring patients for retained products of conception
Aiding in the diagnosis of gestational trophoblastic disease (GTD), testicular tumors, ovarian germ cell tumors, teratomas, and, rarely, other human chorionic gonadotropin (hCG)-secreting tumors
Serial measurement of hCG following treatment for:
-Monitoring therapeutic response in GTD or in hCG-secreting tumors
-Detecting persistent or recurrent GTD or hCG-secreting tumors
This test is not intended to detect or monitor pregnancy.
Method Name
Electrochemiluminescence Immunoassay (ECLIA)
Reporting Name
Beta-HCG, Quantitative, SSpecimen Type
SerumOrdering Guidance
If human chorionic gonadotropin (hCG) during pregnancy is indicated, order THCG / Human Chorionic Gonadotropin (hCG), Quantitative, Pregnancy, Serum.
If hCG testing requested on cerebrospinal fluid specimens to aid in the diagnosis of brain metastases of testicular cancer or extragonadal intracerebral germ cell tumors, order BHSF / Beta-Human Chorionic Gonadotropin, Quantitative, Spinal Fluid.
Specimen Required
Patient Preparation: For 12 hours before specimen collection, patient should not take multivitamins or dietary supplements (eg, hair, skin, and nail supplements) containing biotin (vitamin B7).
Supplies: Sarstedt Aliquot Tube, 5 mL (T914)
Collection Container/Tube:
Preferred: Serum gel
Acceptable: Red top
Submission Container/Tube: Plastic vial
Specimen Volume: 1 mL
Collection Instructions: Centrifuge and aliquot serum into a plastic vial.
Specimen Minimum Volume
0.75 mL
Specimen Stability Information
Specimen Type | Temperature | Time | Special Container |
---|---|---|---|
Serum | Refrigerated (preferred) | 7 days | |
Frozen | 90 days | ||
Ambient | 7 days |
Reject Due To
Gross hemolysis | Reject |
Gross lipemia | OK |
Reference Values
Children(1,2)
Males
Birth-3 months: ≤50 IU/L*
>3 months-<18 years: <1.4 IU/L
Females
Birth-3 months: ≤50 IU/L*
>3 months-<18 years: <1.0 IU/L
*Human chorionic gonadotropin (hCG), produced in the placenta, partially passes the placental barrier. Newborn serum beta-hCG concentrations are approximately 1/400th of the corresponding maternal serum concentrations, resulting in neonate beta-hCG levels of 10-50 IU/L at birth. Clearance half-life is approximately 2 to 3 days. Therefore, by 3 months of age, levels comparable to adults should be reached.
Adults (97.5th percentile)
Males: <1.4 IU/L
Females
Premenopausal, nonpregnant: <1.0 IU/L
Postmenopausal: <7.0 IU/L
Pediatric reference values based on:
1. Chen RJ, Huang SC, Chow SN, Hsieh CY. Human chorionic gonadotropin pattern in maternal circulation. Amniotic fluid and fetal circulation in late pregnancy. J Reprod Med. 1993;38(2):151-154
2. Schneider DT, Calaminus G, Göbel U. Diagnostic value of alpha 1-fetoprotein and beta-human chorionic gonadotropin in infancy and childhood. Pediatr Hematol Oncol. 2001;18(1):11-26
Interpretation
After delivery, miscarriage, or pregnancy termination, human chorionic gonadotropin (hCG) falls with a half-life of 24 to 36 hours, until prepregnancy levels are reached. An absent or significantly slower decline is seen in patients with retained products of conception.
Gestational trophoblastic disease (GTD) is associated with very considerable elevations of hCG, usually above 2 multiples of the medians for gestational age persisting or even rising beyond the first trimester.
Serum hCG levels are elevated in approximately 40% to 50% of patients with nonseminomatous testicular cancer and 20% to 40% of patients with seminoma. Markedly elevated levels of hCG (>5000 IU/L) are uncommon in patients with pure seminoma and indicate the presence of a mixed testicular cancer.
Ovarian germ cell tumors (approximately 10% of ovarian tumors) display elevated hCG levels in 20% to 50% of cases. Teratomas in children may overproduce hCG, even when benign, resulting in precocious pseudopuberty. Levels may be elevated to similar levels as seen in testicular cancer.
Among nonreproductive tumors, hepatobiliary tumors (hepatoblastomas, hepatocellular carcinomas, and cholangiocarcinomas) and neuroendocrine tumors (eg, islet cell tumors and carcinoids) are those most commonly associated with hCG production.
Many hCG-producing tumors also produce other embryonic proteins or antigens, in particular alpha fetoprotein (AFP). AFP should, therefore, also be measured in the diagnostic workup of such neoplasms.
Complete therapeutic response in hCG-secreting tumors is characterized by a decline in hCG levels with an apparent half-life of 24 to 36 hours and eventual return to concentrations within the reference range. GTD and some tumors may produce hyperglycosylated hCG with a longer half-life, but an apparent half-life of more than 3 days suggests the presence of residual hCG-producing tumor tissue.
A rise in hCG levels above the reference range in patients with hCG-producing tumors that had previously been treated successfully, suggests possible local or distant metastatic recurrence.
Day(s) Performed
Monday through Saturday
Report Available
1 to 3 daysSpecimen Retention Time
3 monthsTest Classification
This test has been modified from the manufacturer's instructions. Its performance characteristics were determined by Mayo Clinic in a manner consistent with CLIA requirements. This test has not been cleared or approved by the US Food and Drug Administration.CPT Code Information
84702
LOINC Code Information
Test ID | Test Order Name | Order LOINC Value |
---|---|---|
BHCG | Beta-HCG, Quantitative, S | 21198-7 |
Result ID | Test Result Name | Result LOINC Value |
---|---|---|
BHCG | Beta-HCG, Quantitative, S | 21198-7 |
Forms
If not ordering electronically, complete, print, and send an Oncology Test Request (T729) with the specimen.