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Jessica M. Faupel-Badger, Barbara J. Fuhrman, Xia Xu, Roni T. Falk, Larry K. Keefer, Timothy D. Veenstra, Robert N. Hoover, and Regina G. Ziegler
Source: Cancer Epidemiol Biomarkers Prev. 2010 January ; 19(1): 292–300. doi:10.1158/1055-9965.EPI-09-0643.
Abstract
Absolute and relative concentrations of estrogens and estrogen metabolites (EM) are important for clinical decisions, as well as for epidemiologic, experimental, and clinical research on hormonal carcinogenesis. Radioimmunoassays (RIA) and enzyme-linked immunosorbent assays (ELISA) are routinely used for measuring EM in blood and urine due to efficiency and low cost. Here we compare absolute and ranked concentrations of estrone, estradiol, and estriol measured by indirect RIA and of 2-hydroxyestrone and 16α-hydroxyestrone measured by ELISA to the concentrations obtained using a novel liquid-chromatography-tandem mass spectrometry (LC-MS/MS) method which measures 15 EM concurrently.
We used overnight urine samples collected from control women (362 premenopausal, 168 postmenopausal) participating in a population-based case-control study of breast cancer among Asian-American women ages 20–55 years. When comparing RIA or ELISA levels to LC-MS/MS, absolute concentrations for the five EM ranged from 1.6–2.9 and 1.4–11.8 times higher in premenopausal and postmenopausal women, respectively, (all p<0.0001). However, LC-MS/MS measurements were highly correlated [Spearman r (rs) =0.8–0.9] with RIA and ELISA measurements in premenopausal women, and moderately correlated (rs=0.4–0.8) in postmenopausal women. Measurements of the 2-hydroxyestrone:16α-hydroxyestrone ratio, a putative biomarker of breast cancer risk, were moderately correlated in premenopausal women (rs=0.6–0.7) but only weakly correlated in postmenopausal women (rs=0.2). LC-MS/MS had higher intraclass correlation coefficients (≥99.6%) and lower coefficients of variation (≤9.4%) than ELISA (≥97.2% and ≤14.2%) and RIA (≥95.2% and ≤17.8%).
Comparison with the LC-MS/MS method suggests that the widely used RIA and ELISA EM measures may be problematic, especially at low EM levels characteristic of postmenopausal women.
J Am Pharm Assoc. 2003;43:724–6. – Jolena Hagen, Nicolette Gott, and Donald R. Miller
Recent reports concerning the safety of hormone replacement therapy (HRT) have led many women to seek alternative ways to treat menopausal symptoms. A new alternative that has become very popular is bioidentical HRT. This therapy is often based on the results of saliva hormone tests, which may be purchased from pharmacies and physician offices or over the Internet. Compounding pharmacies individualize HRT based on the results of these tests. Although saliva hormone testing is easy and convenient for a patient to perform at home, it has potential problems.2–4 Given the importance of these tests to compounding pharmacists, we decided to perform a simple check on the tests’ reliability.
Conclusion: Our findings suggest that laboratory values for saliva hormone samples collected with at-home test kits are not reliable. The individualization of HRT for patients is impossible without a reliable analysis. We suggest that compounding pharmacists periodically send in replicates of their own samples to test the reliability of the laboratories that they use.
Source: Cancer Epidemiol Biomarkers Prev. 2008 December ; 17(12): 3411–3418. doi: 10.1158/1055-9965.EPI-08-0355. RT Falk1, X Xu2, L Keefer3, TD Veenstra2, and RG Ziegler1
Abstract
Background—Accurate, reproducible, and sensitive measurements of endogenous estrogen exposure and individual patterns of estrogen metabolism are needed for etiologic studies of breast cancer. We have developed a high performance liquid chromatography-tandem mass spectrometry (LC-MS/MS) method to quantitate simultaneously 15 urinary estrogens and estrogen metabolites (EM): estrone (E1); estradiol (E2); three catechol estrogens; five estrogens in the 16α pathway, including estriol (E3); and five methoxy estrogens.
Methods—Overnight urines were obtained from 45 participants. For the reproducibility study, two blinded, randomized aliquots from 5 follicular and 5 luteal premenopausal women, 5 naturally postmenopausal women, and 5 men were assayed in each of four batches. Assay coefficients of variation (CVs) and intraclass correlation coefficients (ICCs) were calculated with analysis of variance models. Data from the additional 25 participants were added to compare EM levels by menstrual/sex group and assess inter-individual variability. Results—For each EM, overall CVs were ≤10%. ICCs for each menstrual/sex group were generally ≥98%. Although geometric mean EM concentrations differed among the four groups, rankings were similar, with E3, 2-hydroxyestrone, E1, E2, and 16-ketoestradiol accounting for 60–75% of total urinary EM. Within each group, inter-individual differences in absolute concentrations were consistently high; the range was 10–100 fold for nearly all EM.
Conclusion—Our LC-MS/MS method for measuring 15 urinary EM is highly reproducible, and the range of EM concentrations in each menstrual/sex group is quite large relative to assay variability. Whether these patterns persist in blood and target tissues awaits further development and application of this method.
Jurczak A, Brodowski J, Grochans E, Karakiewicz B, Szkup-Jabłońska M, Wieder-Huszla S, Mroczek B, Włoszczak-Szubzda A, Grzywacz A
Source: Laboratory of Propaedeutics in Nursing, Pomeranian Medical University, Szczecin, Poland. Ann Agric Environ Med. 2013 Mar 25; 20(1):147-51.
Abstract
Introduction and objective: The level of trace elements is extremely important for the maintenance of normal functioning of the human body. The risk of disturbance of their balance increases especially dynamically during the period of menopause. The objective of the study was the effect of MHT on the levels of bioelements (Mg and Zn) in blood plasma, and toxic metals (Pb and Cd) in the whole blood in postmenopausal women. Materials and methods: The study covered 323 women at postmenopausal age from the population of the West Pomeranian Region, in whom the levels of Mg, Zn, Pb and Cd were determined. The women were divided into two groups: study and control. The study group was 152 women who used menopausal hormone therapy (MHT). The control group was 171 women who did not use MHT, and had had their final menstrual period at least one year prior to inclusion in the study. The mean age of the women examined was 56±5. Results: Significantly higher levels of the bioelements Mg, Zn were observed in women who used MHT, compared to the control group (p<0.05). The concentration of Pb in whole blood was significantly lower in the study than the control group: 16.09±7.33 µg/l and 20.18±9.01 µg/l, respectively. An elevated level of Cd in whole blood was found in both groups of women: 0.9±1.03 µg/l and 0.8±1.1 µg/l, respectively. It was noted that women who used MHT more frequently declared the presence of climacteric symptoms (p<0.05). Conclusions: 1) Higher levels of Mg and Zn were found in blood plasma of women who used MHT. 2) The mean concentration of Cd in the blood of women in both groups was similar. 3) In women who use MHT the level of Pb in whole blood was lower, compared to the rest of the women.
