Channing Laboratory, Department of Medicine, Harvard Medical School and Brigham and Women's Hospital, Boston, MA 02115, USA.
Horm Cancer. 2010 Feb;1(1):2-10. doi: 10.1007/s12672-009-0003-0. Epub 2010 Feb 9.
Evidence from both laboratory and epidemiologic studies indicate a key role of hormones in the etiology of breast cancer. In epidemiologic studies, indirect data, including the consistent associations observed between reproductive factors and breast cancer risk, support an important contribution of hormones to risk. Recently, the associations between circulating hormones in premenopausal women and subsequent risk of breast cancer have been evaluated. To date, both positive and null associations have been observed for estrogens and inverse and null associations for progesterone with breast cancer risk. For estrogens, the relationships may vary by menstrual cycle phase (e.g., follicular versus luteal phase), although this requires confirmation. Few studies have evaluated estrogen metabolites in relation to breast cancer risk; hence, no conclusions can yet be drawn. Findings for the largely adrenal-derived dehydroepiandrosterone (DHEA) and DHEA sulfate also are inconsistent and may vary by age. However, relatively consistent positive associations have been observed between testosterone (or free testosterone) levels and breast cancer risk; these associations are of similar magnitude to those confirmed among postmenopausal women. In this review, we summarize current evidence and identify gaps and inconsistencies that need to be addressed in future studies of sex steroids and premenopausal breast cancer risk.
来自实验室和流行病学研究的证据表明，激素在乳腺癌的病因学中起着关键作用。在流行病学研究中，间接数据，包括观察到的生殖因素与乳腺癌风险之间的一致关联，支持激素对风险的重要贡献。最近，已经评估了绝经前妇女循环激素与随后乳腺癌风险之间的关联。迄今为止，雌激素与乳腺癌风险呈正相关和零相关，而孕激素与乳腺癌风险呈负相关和零相关。对于雌激素，其关系可能因月经周期阶段（例如，卵泡期与黄体期）而异，尽管这需要确认。很少有研究评估雌激素代谢物与乳腺癌风险的关系；因此，目前还不能得出结论。脱氢表雄酮（DHEA）和 DHEA 硫酸盐的主要肾上腺来源的研究结果也不一致，并且可能因年龄而异。然而，在睾酮（或游离睾酮）水平与乳腺癌风险之间观察到相对一致的正相关；这些关联与绝经后妇女中证实的关联相似。在这篇综述中，我们总结了当前的证据，并确定了需要在未来关于性激素和绝经前乳腺癌风险的研究中解决的差距和不一致。
