Estrogens, Estrone (E1) and Estradiol (E2), Fractionated, Serum
Synonym(s)
Estradiol; Estrogens, total; Estrone; Total Estrogens; E1 (Estrone)
Test ID
ESTF
General Information
Useful for:
Simultaneous high-sensitivity determination of serum estrone and estradiol levels
Situations requiring either higher sensitivity estradiol measurement, estrone measurement, or both, including:
As part of the diagnosis and workup of precocious and delayed puberty in females and, to a lesser degree, males
As part of the diagnosis and workup of suspected disorders of sex steroid metabolism, eg, aromatase deficiency and 17 alpha-hydroxylase deficiency
As an adjunct to clinical assessment, imaging studies, and bone mineral density measurement in the fracture risk assessment of postmenopausal women and, to a lesser degree, older men
Monitoring low-dose female hormone replacement therapy in postmenopausal women
Applications that require moderately sensitive measurement of estradiol including:
Evaluation of hypogonadism and oligo-amenorrhea in females
Assessing ovarian status, including follicle development, for assisted reproduction protocols (eg, in vitro fertilization)
In conjunction with luteinizing hormone measurements, monitoring of estrogen replacement therapy in hypogonadal premenopausal women
Evaluation of feminization, including gynecomastia, in males
Diagnosis of estrogen-producing neoplasms in males, and, to a lesser degree, females
Specimen Type
Serum
Specimen Requirements
Red Top
Minimum Sample Volume
0.8 mL
Additional Processing Details
Centrifuge and aliquot serum in plastic vial within 2 hours of collection
Stability
Refrigerated (preferred): 28 days
Ambient: 28 days
Frozen: 28 days
Unacceptable Specimen Conditions
Serum Gel (SST)
Limitations
Fulvestrant is a member of a new class of drugs called “selective estrogen receptor degraders“ (SERDS). Fulvestrant has modest cross-reactivity (1%-5%) in estradiol immunoassays, but because the peak dose levels of this drug are between 10-fold (reproductive age women) and more than 200-fold (postmenopausal women) higher than the naturally circulating estradiol concentrations in the treated women, this causes dramatically false-high results in estradiol immunoassays, when blood sampling occurs in close temporal proximity to dosing. By contrast, estradiol measurements by mass spectrometry display more than 1000-fold lower cross-reactivity (<0.001%), meaning that the impact of Fulvestrant on serum estradiol measurements by mass spectrometry is negligible, even if blood sampling occurs at peak dose.
Methodology
Liquid Chromatography-Tandem Mass Spectrometry (LC-MS/MS)
Estimated TAT
2-4 days
Testing Schedule
Monday-Saturday
Test Includes
E1 Estrone EEST Estradiol, Mass Spectrometry
Retention
14 days
CPT Code(s)
82670; 82671; 82679
Reference Range
Gender
Tanner Stage
Mean Age (years)
E1: Estrone (pg/mL)
E2: Estradiol (pg/mL)
Males
Stage I (>14 days and prepubertal)
7.1
< 16
< 13
Stage II*
11.5
< 22
< 16
Stage III
13.6
10 - 25
< 26
Stage IV
15.1
10 - 46
< 38
Stage V
18.0
10 - 60
10 - 40
Adult
10 - 60
10 - 40
Females
Stage I (>14 days and prepubertal)
7.1
< 29
< 20
Stage II**
10.5
10 - 33
< 24
Stage III
11.6
15 - 43
< 60
Stage IV
12.3
16 - 77
15 - 85
Stage V
14.5
17 - 200
15 - 350***
Adult - Premenopausal
17 - 200
15 - 350***
Adult - Postmenopausal
7 - 40
< 10
Newborns (1-14 days): Estrone & Estradiol levels in newborns are both very elevated at birth but will fall to prepubertal levels within a few days
* Boys: Puberty onset (transition from Tanner stage I to Tanner stage II) occurs for boys at a median age of 11.5 (+/- 2) years. For boys there is no proven relationship between puberty onset and body weight or ethnic origin. Progression through Tanner stages is variable. Tanner stage V (adult) should be reached by age 18
** Girls: Puberty onset (transition from Tanner stage I to Tanner stage II) occurs for girls at a median age of 10.5 (+/- 2) years. There is evidence that it may occur up to 1 year earlier in obese girls and in African American girls. Progression through Tanner stages is variable. Tanner stage V (adult) should be reached by age 18.
*** E2 levels vary widely through the menstrual cycle
The reference ranges for children are based on the published literature,(1,2) cross-correlation of our assay with assays used to generate the literature data and on our data for young adults.
Conversion-factor E1: pg/mL x 3.704=pmol/L (molecular weight=270)
Conversion factor E2: pg/mL x 3.676=pmol/L (molecular weight=272)
