The injectable contraceptive depot medroxy-progesterone acetate (DMPA) (Depo-Provera) is commonly used by women worldwide, and it contains the same progestin that is most commonly used in combined estrogen and progestin hormonal therapy (CHT) regimens taken by postmenopausal women in the United States. Data from several recent studies indicate that CHT increases a woman's risk of breast cancer, and that the progestin component of CHT may be particularly important with respect to this increased risk. There are limited data on the relationship between DMPA and breast cancer risk though. The available evidence suggests that current DMPA use is associated with a 1.5 to 1.65-fold increased risk of breast cancer. However, additional studies of the relationship between DMPA use and breast cancer are needed because these studies had methodologic limitations (sample size and/or study design issues), none were conducted in the U.S. and so it is unclear whether or not these results are generalizable to U.S. women (since reproductive and contraceptive patterns vary widely by country), and little is known about mechanisms through which DMPA promotes breast cancer. This study is worthwhile even if we find that there is no association between DMPA and breast cancer risk, since in this case women using DMPA will be reassured that using the same drug that has been implicated as a cause of breast cancer does not also increase their breast cancer risk when taken as an injectable contraceptive. Herein we propose a case-control study of 1,000 women aged 20-44 who have been diagnosed with breast cancer and 1,000 population-based controls who reside in the Seattle-Puget Sound area. The specific hypotheses to be tested are: (1) Is DMPA use associated with an increased risk of breast cancer in premenopausal women 20-44? Does the duration and/or recency of DMPA use influence the magnitude of this association?; (2) Do demographic, reproductive, or anthropometric characteristics, such as parity and body mass index, modify this association?; and (3) Does the association between DMPA and breast cancer risk vary by histologic type or by the expression of steroid receptors including ERq, ERft, and PR?

Agency
National Institute of Health (NIH)
Institute
National Cancer Institute (NCI)
Type
Research Project (R01)
Project #
1R01CA105041-01A2
Application #
6918464
Study Section
Epidemiology of Cancer Study Section (EPIC)
Program Officer
Silkensen, Shannon M
Project Start
2005-09-26
Project End
2010-06-30
Budget Start
2005-09-26
Budget End
2006-06-30
Support Year
1
Fiscal Year
2005
Total Cost
$674,271
Indirect Cost
Name
Fred Hutchinson Cancer Research Center
Department
Type
DUNS #
078200995
City
Seattle
State
WA
Country
United States
Zip Code
98109
Baglia, Michelle L; Malone, Kathleen E; Tang, Mei-Tzu C et al. (2017) Alcohol Intake and Risk of Breast Cancer by Histologic Subtype and Estrogen Receptor Status Among Women Aged 55 to 74 Years. Horm Cancer 8:211-218
Kawai, Masaaki; Malone, Kathleen E; Tang, Mei-Tzu C et al. (2014) Active smoking and the risk of estrogen receptor-positive and triple-negative breast cancer among women ages 20 to 44 years. Cancer 120:1026-34
Kawai, Masaaki; Malone, Kathleen E; Tang, Mei-Tzu C et al. (2014) Height, body mass index (BMI), BMI change, and the risk of estrogen receptor-positive, HER2-positive, and triple-negative breast cancer among women ages 20 to 44 years. Cancer 120:1548-56
Beaber, Elisabeth F; Malone, Kathleen E; Tang, Mei-Tzu Chen et al. (2014) Oral contraceptives and breast cancer risk overall and by molecular subtype among young women. Cancer Epidemiol Biomarkers Prev 23:755-64
Li, Christopher I; Daling, Janet R; Haugen, Kara L et al. (2014) Use of menopausal hormone therapy and risk of ductal and lobular breast cancer among women 55-74 years of age. Breast Cancer Res Treat 145:481-9
Li, Christopher I; Beaber, Elisabeth F; Tang, Mei-Tzu Chen et al. (2013) Reproductive factors and risk of estrogen receptor positive, triple-negative, and HER2-neu overexpressing breast cancer among women 20-44 years of age. Breast Cancer Res Treat 137:579-87
Li, Christopher I; Daling, Janet R; Tang, Mei-Tzu C et al. (2013) Use of antihypertensive medications and breast cancer risk among women aged 55 to 74 years. JAMA Intern Med 173:1629-37
Li, Christopher I; Beaber, Elisabeth F; Tang, Mei Tzu Chen et al. (2012) Effect of depo-medroxyprogesterone acetate on breast cancer risk among women 20 to 44 years of age. Cancer Res 72:2028-35
Voigt, Lynda F; Schwartz, Stephen M; Doody, David R et al. (2011) Feasibility of including cellular telephone numbers in random digit dialing for epidemiologic case-control studies. Am J Epidemiol 173:118-26