Postmenopausal estrogen and progestin use in relation to breast cancer risk.

作者：Polly A. Newcomb, Linda T. Titus-Ernstoff, Kathleen M. Egan, Amy Trentham‐Dietz, John A. Baron, Barry E. Storer, Walter Churchill Willett, Meir J. Stampfer · 发表于：PubMed · 年份：2002 · 被引用次数：183 · 研究领域：Cancer Risks and Factors、Estrogen and related hormone effects、Menopause: Health Impacts and Treatments

Epidemiological evidence now consistently supports a modest increase in breast cancer risk among women using postmenopausal hormones, usually estrogens. Less is known regarding how the addition of progestin affects breast cancer risk. The objective of this study was to investigate the type and duration of postmenopausal therapy and breast cancer risk. We performed a multicenter population-based case-control study set in Massachusetts, New Hampshire, and Wisconsin. The subjects were 5298 postmenopausal women (age range, 50-79 years) with a new diagnosis of invasive breast cancer from statewide tumor registries. For comparison, 5571 controls were randomly selected from population lists. Participants completed a structured telephone interview covering hormone use and breast cancer risk factors. Multivariable regression models were used to estimate relative risks (RRs) and 95% confidence intervals (CIs). The RR for breast cancer increased with longer durations of hormone use, about 2%/year for estrogen alone (RR, 1.02; 95% CI, 1.01-1.03) and 4%/year for estrogen-progestin use (RR, 1.04; 95% CI, 1.01-1.08). Estrogen-progestin use that was both recent and long term (>5 years in duration) was more strongly associated with breast cancer risk (RR, 1.57; 95% CI, 1.15-2.14) than similar use of estrogen alone (RR, 1.39; 95% CI, 1.17-1.65). In estrogen-progestin users, risks were similar for sequential and continuous use regimens but perhaps stronger for lobular than ductal breast cancer....