Estradiol Testing in Men
Estradiol in Men: Optimal Testing Recommendations
- Measurement of estradiol in men (and children) should be performed by a sensitive liquid chromatography-tandem mass spectrometry (LC/MS)-based assay.
- Immunoassay-based estradiol tests perform best at higher concentrations of estradiol and therefore work well for those with levels in the adult-female range.
Guidelines for Test Utilization
- What does the test tell me?
- When should I order this test?
- When should I NOT order this test?
- How should I interpret the result?
- Is the test result diagnostic/confirmatory of the condition? If not, is there a diagnostic/confirmatory test?
- Are there factors that can affect the lab result?
- Are there considerations for special populations?
- What other test(s) might be indicated?
What does the test tell me?
This test, when measured by LC/MS, produces an accurate and sensitive quantitation of estradiol in circulation. If above the sex- and age-appropriate reference interval, this may be an indicator of a feminizing adrenal tumor. Estradiol values below the reference interval are consistent with deficiency from aromatase inhibitors, either congenital or acquired. [back to top]
When should I order this test?
Estradiol by LC/MS in men should be used to evaluate men with symptoms of estradiol excess (primarily manifest as gynecomastia), steroid-secreting adrenal, hepatic, or testicular tumors or estradiol deficiency (decreased libido, low bone density, and increased body fat. Estradiol may also be followed in men receiving testosterone replacement therapy. [back to top]
When should I NOT order this test?
Do not order estradiol or other estrogens by immunoassay on men, children, and postmenopausal women. [back to top]
How should I interpret the result?
Estradiol in men should be interpreted in light of sex- and age-appropriate reference intervals. Values above or below the reference interval likely indicate estrogen excess or deficiency, respectively. [back to top]
Is the test result diagnostic/confirmatory of the condition? If not, is there a diagnostic/confirmatory test?
Estradiol results alone are not particularly indicative of any specific disease or disorder. Additional testing is necessary to elucidate the cause of specific symptoms (see "What other tests might be indicated?"). [back to top]
Are there factors that can affect the lab result?
Immunoassay testing of estradiol is generally only appropriate for concentrations over around 50 pg/mL, otherwise immunoassays tend to overestimate the actual concentration. Therefore, individuals with low concentrations of estradiol should not have it measured by immunoassay. Groups with low estradiol levels include men, children, postmenopausal women, and women treated with aromatase inhibitors. Additionally, Fulvestrant, a selective estrogen receptor degrader class of drug, has been shown to cross react with estrogen immunoassays, and therefore those taking this drug should not have estrogen measured by immunoassay. [back to top]
Are there considerations for special populations?
Children and post-menopausal women also have low circulating estradiol and therefore also require testing by LC/MS. [back to top]
What other test(s) might be indicated?
Other tests to order depends upon the patient's symptoms: decreased libido may also necessitate total and possibly free testosterone, prolactin, follicle stimulating hormone (FSH), and luteinizing hormone (LH) testing. Low bone density may require imaging-based assessment, such as dual-energy x-ray absorptiometry (DEXA). Gynecomastia evaluation should include testing for other causes, including hypogonadism, cirrhosis, testicular tumors, or thyroid disease. [back to top]
