151
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Santen RJ. Assessing individual risk for breast cancer: role of oestrogens and androgens. Breast Cancer Res 2008; 10 Suppl 4:S10. [PMID: 19128423 PMCID: PMC2614836 DOI: 10.1186/bcr2170] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Affiliation(s)
- Richard J Santen
- University of Virginia Health Sciences System, Charlottesville, VA 22908-1416, USA.
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152
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Santen RJ, Lee JS, Wang S, Demers LM, Mauras N, Wang H, Singh R. Potential role of ultra-sensitive estradiol assays in estimating the risk of breast cancer and fractures. Steroids 2008; 73:1318-21. [PMID: 18614192 DOI: 10.1016/j.steroids.2008.05.008] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/13/2008] [Revised: 05/19/2008] [Accepted: 05/20/2008] [Indexed: 11/20/2022]
Abstract
Radioimmunoassays (RIA) for the measurement of estradiol are sufficiently sensitive to assess the reproductive status of pre-menopausal women but lack sufficient sensitivity for low concentrations found in post-menopausal women. Bioassays have been used in the past to measure low estrogen levels but are impractical for handling high volumes of tests, particularly routine and non-research specimens. In this study, we compared results for estradiol using several different methods including bioassay, RIA, and two tandem mass spectrometry methods. At the lower tertile of estradiol measurements by RIA, the overall excellent correlation with results obtained by tandem mass spectrometry (i.e. r=0.83) was lost (i.e. r=0.29). In addition, results were much lower with bioassay and mass spectrometry than with RIA suggesting that RIA measures undesired noise or estrogen metabolites. The mass spectrometry methods correlate best with isotopic kinetic methods when assessing aromatase inhibition. On this basis, we conclude that mass spectrometry assays are the best option for measurement of low estradiol concentrations. With such assays, greater discrimination should be achievable when using estradiol levels as a predictor of the risks for breast cancer and for fractures.
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Affiliation(s)
- Richard J Santen
- University of Virginia, Charlottesville, VA 22908, United States.
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153
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Abstract
Sex steroid measurements for the investigation of endocrine disorders have been fraught with accuracy and imprecision problems since the advent of high throughput, direct assays almost 10 years ago on automated analyzers. Results from testosterone and estradiol measurements at the low end of detectability have suffered the most and there are few automated systems that can accurately measure these steroids in women, children and hypogonadal males on a routine basis. With the advent of mass spectrometry coupled to either gas chromatography or liquid chromatography, an improved approach to the measurement of these steroids has developed that shows promise for accurately and precisely measuring testosterone and estradiol in all patient populations including women and children. These mass spectrometry based methods for the sex steroids have been established as higher order reference method procedures that will resolve the issues of low end sensitivity measurements for these steroids, provide for appropriate standardization and reference materials and align most laboratories in hospital and reference laboratories to generate results that are inter-changeable between laboratories and methods.
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Affiliation(s)
- Laurence M Demers
- Penn State University College of Medicine, The M.S. Hershey Medical Center, Hershey, PA 17033, United States.
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154
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Vesper HW, Botelho JC, Shacklady C, Smith A, Myers GL. CDC project on standardizing steroid hormone measurements. Steroids 2008; 73:1286-92. [PMID: 18834895 DOI: 10.1016/j.steroids.2008.09.008] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/18/2008] [Accepted: 09/18/2008] [Indexed: 10/21/2022]
Abstract
Estradiol and testosterone measurements are widely used to assess steroid hormone status and to monitor stimulative, suppressive, or replacement therapy among children and adults of both sexes. Despite their common application, these measurements - particularly at low concentrations - show only limited comparability among assays, such as those observed for testosterone among women or for estradiol among postmenopausal women. This shortcoming hampers progress in research and in research translation. To overcome this, the Centers for Disease Control and Prevention, National Center for Environmental Health, Division of Laboratory Sciences (CDC/NCEH/DLS) initiated a project to standardize and to improve steroid hormone measurements. The project is a collaborative effort between institutions, organizations, and groups involved in estradiol and testosterone testing, test interpretation, and use. Specific activities are scheduled based on needs assessments conducted with the clinical, research, and public health communities. The initial focus of this standardization project is to improve analytical measurements through reference laboratory activities. As part of the project's translational activities, CDC/NCEH/DLS will work further with professional societies and organizations to improve pre- and postanalytical issues that affect results from these measurements and their interpretation.
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Affiliation(s)
- Hubert W Vesper
- Centers for Disease Control and Prevention, Division of Laboratory Sciences, 4770 Buford Hwy NE MS F25, Atlanta, GA 30341, United States.
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155
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Thienpont LM, Van Uytfanghe K, Blincko S, Ramsay CS, Xie H, Doss RC, Keevil BG, Owen LJ, Rockwood AL, Kushnir MM, Chun KY, Chandler DW, Field HP, Sluss PM. State-of-the-Art of Serum Testosterone Measurement by Isotope Dilution–Liquid Chromatography– Tandem Mass Spectrometry. Clin Chem 2008; 54:1290-7. [DOI: 10.1373/clinchem.2008.105841] [Citation(s) in RCA: 119] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Abstract
Background: The recent interest of clinical laboratories in developing serum testosterone assays based on isotope dilution–liquid chromatography–tandem mass spectrometry (ID-LC-MS/MS) stems from the lack of accuracy of direct immunoassays. In this study, we assessed the accuracy and state of standardization (traceability) of 4 published ID-LC-MS/MS procedures in a method comparison with an ID–gas chromatography (GC)–MS reference measurement procedure listed in the database of the Joint Committee for Traceability in Laboratory Medicine.
Methods: The study used 58 specimens from different patient categories. Each specimen was measured in triplicate (ID-LC-MS/MS) and quadruplicate (ID-GC-MS) in independent runs.
Results: The testosterone concentrations by ID-GC-MS were 0.2–4.4 nmol/L (women), 0.2–2.0 nmol/L (hypogonadal man), and 10.1–31.3 nmol/L (normogonadal men). For ID-GC-MS, the CV was nearly constant, with a median of 1.0%; for ID-LC-MS/MS, it was concentration-dependent, with a median of up to 8%. Weighted Deming regression gave mean slopes, intercepts, and correlation coefficients of 0.90–1.11, −0.055–0.013 nmol/L, and 0.993–0.997, respectively. The % difference plot showed between 7% and 26% of the results outside a total error limit of 14%, with median deviations from ID-GC-MS between −9.6 and 0.4%.
Conclusions: This study demonstrated fairly good accuracy and standardization of the tested ID-LC-MS/MS procedures. Performance differences between procedures were evident in some instances, due to improper calibration and between-run calibration control. This emphasizes the need for thorough validation, including traceability, of new ID-LC-MS/MS procedures.
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Affiliation(s)
- Linda M Thienpont
- Laboratory for Analytical Chemistry, Faculty of Pharmaceutical Sciences, Gent University, Gent, Belgium
| | - Katleen Van Uytfanghe
- Laboratory for Analytical Chemistry, Faculty of Pharmaceutical Sciences, Gent University, Gent, Belgium
| | | | | | - Hui Xie
- Abbott Diagnostics, Abbott Park, IL
| | | | - Brian G Keevil
- Department of Biochemistry, University Hospital of South Manchester, Manchester, UK
| | - Laura J Owen
- Department of Biochemistry, University Hospital of South Manchester, Manchester, UK
| | - Alan L Rockwood
- ARUP Laboratories, Salt Lake City, UT
- Department of Pathology, University of Utah School of Medicine, Salt Lake City, UT
| | | | | | | | - Helen P Field
- Department of Clinical Biochemistry, Old Medical School, Leeds General Infirmary, Leeds, UK
| | - Patrick M Sluss
- Clinical Pathology Core Laboratory, Massachusetts General Hospital, Boston, MA
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156
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Waaseth M, Bakken K, Dumeaux V, Olsen KS, Rylander C, Figenschau Y, Lund E. Hormone replacement therapy use and plasma levels of sex hormones in the Norwegian Women and Cancer postgenome cohort - a cross-sectional analysis. BMC WOMENS HEALTH 2008; 8:1. [PMID: 18194511 PMCID: PMC2254595 DOI: 10.1186/1472-6874-8-1] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/26/2007] [Accepted: 01/14/2008] [Indexed: 12/21/2022]
Abstract
Background Hormone replacement therapy use (HRT) is associated with increased breast cancer risk. Our primary objective was to explore hormone levels in plasma according to HRT use, body mass index (BMI) and menopausal status. A secondary objective was to validate self-reported questionnaire information on menstruation and HRT use in the Norwegian Women and Cancer postgenome cohort (NOWAC). Methods We conducted a cross-sectional study of sex hormone levels among 445 women aged 48–62 who answered an eight-page questionnaire in 2004 and agreed to donate a blood sample. The samples were drawn at the women's local general physician's offices in the spring of 2005 and sent by mail to NOWAC, Tromsø, together with a two-page questionnaire. Plasma levels of sex hormones and Sex Hormone Binding Globulin (SHBG) were measured by immunometry. 20 samples were excluded, leaving 425 hormone measurements. Results 20% of postmenopausal women were HRT users. The plasma levels of estradiol (E2) increased with an increased E2 dose, and use of systemic E2-containing HRT suppressed the level of Follicle Stimulating Hormone (FSH). SHBG levels increased mainly among users of oral E2 preparations. Vaginal E2 application did not influence hormone levels. There was no difference in BMI between HRT users and non-users. Increased BMI was associated with increased E2 and decreased FSH and SHBG levels among non-users. Menopausal status defined by the two-page questionnaire showed 92% sensitivity (95% CI 89–96%) and 73% specificity (95% CI 64–82%), while the eight-page questionnaire showed 88% sensitivity (95% CI 84–92%) and 87% specificity (95% CI 80–94%). Current HRT use showed 100% specificity and 88% of the HRT-users had plasma E2 levels above the 95% CI of non-users. Conclusion Users of systemic E2-containing HRT preparations have plasma E2 and FSH levels comparable to premenopausal women. BMI has an influence on hormone levels among non-users. NOWAC questionnaires provide valid information on current HRT use and menopausal status among Norwegian women who are between 48 and 62 years old.
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Affiliation(s)
- Marit Waaseth
- Institute of Community Medicine, University of Tromsø, Norway.
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