乳腺癌风险与更年期激素治疗相关

gexiaom

乳腺癌风险与更年期激素治疗相关  
In the past decade, results from large prospective cohort studies and the Women's Health Initiative (WHI) randomized placebo-controlled hormone therapy trials have substantially changed thoughts about how estrogen alone and estrogen plus progestin influence the risk of breast cancer, according to a review published in the Journal of The National Cancer Institute.

Although hormone therapy is currently used by millions of women for menopausal symptoms, there is still concern about hormone therapy-induced breast cancer risk. In addition, the effects of estrogen plus progestin vs estrogen alone on breast cancer are not completely understood.

To compare the effects of estrogen alone vs those of estrogen plus progestin on breast cancer risk, Rowan T. Chlebowski, M.D., Ph.D., of the Los Angeles Biomedical Research Institute at Harbor-UCLA Medical Center and Garnet Anderson, Ph.D., at Fred Hutchinson Cancer Research Center at, looked at data from two randomized, placebo-controlled full scale clinical trials conducted in the WHI. One trial evaluated estrogen plus progestin in postmenopausal women with an intact uterus, and the other evaluated estrogen alone in postmenopausal women with prior hysterectomy. Estrogen plus progestin statistically significantly increased the risk of breast cancer. In contrast, estrogen alone use in postmenopausal women with a previous hysterectomy, statistically significantly decreased the risk of breast cancer.

The randomized clinical trial findings differ from the predominance of observational studies, which suggested that both estrogen alone and estrogen plus progestin increase breast cancer incidence. The authors propose that "an imbalance in the use of mammography with greater screening for hormone users could explain some of the increase in breast cancer incidence with estrogen alone seen in cohort studies because screened populations have more cancers detected than unscreened populations".

While the mechanisms underlying the different effects of estrogen alone and estrogen plus progestin are not completely understood, the authors state that preclinical and other clinical evidence suggests "the findings in the clinic, taken together with preclinical evidence, indicate that many breast cancers in post-menopausal women can survive only a limited range of estrogen exposures."

gexiaom

In the past decade, results from large prospective cohort studies and the Women's Health Initiative (WHI) randomized placebo-controlled hormone therapy trials have substantially changed thoughts about how estrogen alone and estrogen plus progestin influence the risk of breast cancer, according to a review published in the Journal of The National Cancer Institute.

美国国立癌症研究所杂志上最近发表的一篇综述，回顾了过去十年的大宗前瞻性对照研究，以及妇女健康倡议协会的随机安慰剂对照的激素治疗实验。当前的激素治疗方法主要有单用雌激素以及雌激素加用孕激素两种。回顾研究的结果大大改变了我们对这两种激素治疗对乳腺癌患病风险的看法。

Although hormone therapy is currently used by millions of women for menopausal symptoms, there is still concern about hormone therapy-induced breast cancer risk. In addition, the effects of estrogen plus progestin vs estrogen alone on breast cancer are not completely understood.

虽然当前激素治疗被广泛应用于妇女的停经后综合征的治疗，但公众对激素治疗是否会增加乳腺癌的患病风险一直存有顾虑。此外，雌激素加用孕激素以及单用雌激素对乳腺癌的影响仍未完全阐明。

To compare the effects of estrogen alone vs those of estrogen plus progestin on breast cancer risk, Rowan T. Chlebowski, M.D., Ph.D., of the Los Angeles Biomedical Research Institute at Harbor-UCLA Medical Center and Garnet Anderson, Ph.D., at Fred Hutchinson Cancer Research Center at, looked at data from two randomized, placebo-controlled full scale clinical trials conducted in the WHI. One trial evaluated estrogen plus progestin in postmenopausal women with an intact uterus, and the other evaluated estrogen alone in postmenopausal women with prior hysterectomy. Estrogen plus progestin statistically significantly increased the risk of breast cancer. In contrast, estrogen alone use in postmenopausal women with a previous hysterectomy, statistically significantly decreased the risk of breast cancer.

来自洛杉矶生物医学研究所的Harbor加州大学洛杉矶分校医学中心的 Rowan T. Chlebowski博士，以及来自Fred Hutchinson癌症研究中心的Garnet Anderson博士，回顾了来自两个妇女健康倡议协会的随机安慰剂对照的大规模临床试验结果，对比单用雌激素以及雌激素加用孕激素对乳腺癌的患病风险影响。其中一个实验研究了雌激素加用孕激素对无子宫手术史的停经后妇女的作用，另外一个实验研究了单用雌激素对有子宫切除手术史的停经后妇女的作用。结果显示，雌激素加用孕激素的治疗会显著增加乳腺癌的患病风险。相比之下，对有子宫切除史的停经后妇女来说，单用雌激素治疗降低了乳腺癌的患病风险。

The randomized clinical trial findings differ from the predominance of observational studies, which suggested that both estrogen alone and estrogen plus progestin increase breast cancer incidence. The authors propose that "an imbalance in the use of mammography with greater screening for hormone users could explain some of the increase in breast cancer incidence with estrogen alone seen in cohort studies because screened populations have more cancers detected than unscreened populations".

在此之前，主流的观测研究结果提示，不管是单用雌激素还是雌激素加用孕激素的治疗，都会增加乳腺癌的发病率，而这些随机临床试验结果却提出了不同的看法。作者提出：“在一些队列研究中观察到单用雌激素增加了乳腺癌发病率，可能是由于这部分人比其他人做了更多的钼靶筛查，而筛查人群比未筛查人群可能会发现更多的肿瘤。”

While the mechanisms underlying the different effects of estrogen alone and estrogen plus progestin are not completely understood, the authors state that preclinical and other clinical evidence suggests "the findings in the clinic, taken together with preclinical evidence, indicate that many breast cancers in post-menopausal women can survive only a limited range of estrogen exposures."

虽然对引起单用雌激素以及雌激素加用孕激素不同作用的机制尚未完全明确，作者提出，“临床前期的证据，和临床发现都显示，许多绝经后妇女罹患的乳腺癌可能只能在一定范围的雌激素水平中生存下来。”

gexiaom

美国国立癌症研究所杂志上最近发表的一篇综述，回顾了过去十年的大宗前瞻性对照研究，以及妇女健康倡议协会的随机安慰剂对照的激素治疗实验。当前的激素治疗方法主要有单用雌激素以及雌激素加用孕激素两种。回顾研究的结果大大改变了我们对这两种激素治疗对乳腺癌患病风险的看法。

虽然当前激素治疗被广泛应用于妇女的停经后综合征的治疗，但公众对激素治疗是否会增加乳腺癌的患病风险一直存有顾虑。此外，雌激素加用孕激素以及单用雌激素对乳腺癌的影响仍未完全阐明。

来自洛杉矶生物医学研究所的Harbor加州大学洛杉矶分校医学中心的 Rowan T. Chlebowski博士，以及来自Fred Hutchinson癌症研究中心的Garnet Anderson博士，回顾了来自两个妇女健康倡议协会的随机安慰剂对照的大规模临床试验结果，对比单用雌激素以及雌激素加用孕激素对乳腺癌的患病风险影响。其中一个实验研究了雌激素加用孕激素对无子宫手术史的停经后妇女的作用，另外一个实验研究了单用雌激素对有子宫切除手术史的停经后妇女的作用。结果显示，雌激素加用孕激素的治疗会显著增加乳腺癌的患病风险。相比之下，对有子宫切除史的停经后妇女来说，单用雌激素治疗降低了乳腺癌的患病风险。

在此之前，主流的观测研究结果提示，不管是单用雌激素还是雌激素加用孕激素的治疗，都会增加乳腺癌的发病率，而这些随机临床试验结果却提出了不同的看法。作者提出：“在一些队列研究中观察到单用雌激素增加了乳腺癌发病率，可能是由于这部分人比其他人做了更多的钼靶筛查，而筛查人群比未筛查人群可能会发现更多的肿瘤。”

虽然对引起单用雌激素以及雌激素加用孕激素不同作用的机制尚未完全明确，作者提出，“临床前期的证据，和临床发现都显示，许多绝经后妇女罹患的乳腺癌可能只能在一定范围的雌激素水平中生存下来。”

gexiaom

全文标题：Does hormone replacement therapy cause breast cancer? An application of causal principles to three studies: Part 1. The Collaborative Reanalysis.
杂志：J Fam Plann Reprod Health Care。2011 Apr;37(2):103-9.
PMID：21454266