众所周知，更年期前后的女性接受雌激素（estrogen）治疗不仅可以减轻“潮热、盗汗”等更年期症状或不适，更可“改善性福与和谐家庭”，但长期以来人们对更年期之女性接受激素替代治疗（Hormone replacement therapy ，HRT）之安全性存在着争议，多数专家认为“更年期之女性接受雌激素治疗，虽可减轻与更年期相关的系列症状和预防骨质疏松，但亦可增加其患乳腺癌、子宫内膜癌、卵巢癌、血栓形成和中风之病症的风险”。据此，专家们建议“更年期之女性慎用雌激素”。

面对如此复杂而又重要的问题，研究人员曾未终止他们的工作。最近，有文献报道“子宫切除的女性，于更年期前后3～5年内仅仅服用雌激素以缓解更年期症状不仅安全，甚至可以降低这类女性患乳腺癌之风险。但仍保留有完整子宫的女性如果想服用雌激素以缓解更年期症状，则应同时服用孕酮，以预防子宫癌。”

尽管北美停经协会（The North American Menopause Society）支持上述观点，但专家们仍然坚持“无论何年龄段的女性，同时接受雌激素＋孕酮治疗不仅增加乳腺癌之风险，亦可增加冠心病、血栓形成和中风等风险。另外，伴乳腺癌易患因素如良性乳腺增生病、乳腺癌家族史等女性，更年期前后接受雌激素替代治疗的风险较大。”

总之，更年期年龄段之女性是否应该接受雌激素等替代治疗，理应在专家的指导下慎重评估后再做出合理的选择！

Estrogen-Only Therapy May Reduce Breast Cancer Risk

Study looked at women with hysterectomy taking hormones for menopause symptoms

TUESDAY, March 6 (HealthDay News) -- Some women who take estrogen-only hormone replacement therapy to stave off hot flashes, night sweats and other symptoms of menopause may be at lower risk for developing breast cancer down the road, a news study says.

Hormone replacement therapy (HRT) fell from grace rather dramatically after a large government-run trial, the U.S. Women's Health Initiative, was stopped early in 2002 because HRT was shown to increase the risk of strokes and breast and ovarian cancer. Since that time, however, some subtleties have emerged as researchers parsed the evidence further. For example, short-term use of HRT is now deemed fairly safe for some women who have severe menopausal symptoms.

The new study shows that longer-term use of estrogen-only therapy may actually lower a woman's odds of developing breast cancer. Estrogen-only therapy is reserved for women who have had a hysterectomy; women with an intact uterus who use HRT must take the hormone progestin with estrogen to prevent uterine cancer.

"Women who have had a hysterectomy may be reassured that taking estrogen by itself, short term, to relieve menopausal symptoms will not increase their risk of breast cancer," said study author Garnet Anderson of the Women's Health Initiative Clinical Coordinating Center at the Fred Hutchinson Cancer Research Center in Seattle. Women should not take estrogen to prevent breast cancer, she stressed.

The new findings were published in the March 7 online edition of The Lancet Oncology.

The North American Menopause Society recently released a position statement that backs up these findings. The group said starting combination hormone therapy (both estrogen and progestin) around the time of menopause to treat symptoms and stave off the brittle-bone disease osteoporosis is safe for some women for three to five years. Estrogen alone can be used for longer than the combination HRT, according to the society.

The new study, which was partially funded by drug manufacturer Wyeth, included more than 7,500 women from the Women's Health Initiative who took estrogen for about six years. Roughly five years after stopping treatment, the women were 23 percent less likely to develop breast cancer when compared to their counterparts who never used HRT.

Women in the estrogen group who did develop breast cancer were 63 percent less likely to die from the disease, compared to women who never took it. The lower risk of breast cancer was seen only among women without risk factors for breast cancer, such as a history of benign breast disease or a strong family history of breast cancer, the study showed.

"The story is pretty clear about estrogen plus progestin -- no matter the age of the women, estrogen plus progestin increases [the risk of] breast cancer, heart disease, stroke and blood clots," Anderson said. "These risks outweigh the benefits for all age groups."

Why estrogen alone may lower breast cancer risk while adding progestin seems to increase the risk is the million dollar question.

"There are hypotheses about the role of estrogen in breasts after a woman has gone through menopause," Anderson said. For example, "her breast tissue, including any precancerous cells, may go through changes as a result of menopause that make them susceptible to estrogen in a way that discourages cell growth."

Estrogen-only therapy is not without risks, however. For estrogen alone, the Women's Health Initiative data showed no overall effect of estrogen on heart disease, but an increased risk of strokes and blood clots.

Women are understandably confused about whether they should take hormones to treat their menopausal symptoms, and for how long they can safely use the therapy.

"The best use of estrogen-alone is in women with a hysterectomy who need relief of hot flashes and night sweats and related menopausal symptoms," Anderson said. These benefits need to be weighed against a woman's risk of stroke or developing blood clots.

Dr. Lila Nachtigall, a professor of obstetrics and gynecology at NYU Langone Medical Center in New York City, agreed that, when used on its own, estrogen can still be safe and effective in treating the symptoms of menopause in women who do not have a uterus.

"It looks very definite that the bad guy is progestin, not estrogen," Nachtigall said. Her advice is to use the lowest effective dose for the shortest amount of time. 　　If more women took estrogen, she said, there would be a dent made in the epidemic of osteoporosis. "Millions of women who never went on estrogen, even for a few years, are really losing bone," she said.

That said, estrogen does increase the risk of blood clots. "Women with blood-clotting disorders should not take it," Nachtigall said.

Commenting on the study, Dr. Stephanie Bernik, chief of surgical oncology at Lenox Hill Hospital in New York City, said, "If you are looking to reduce menopausal symptoms and don't have an intact uterus, [estrogen] is an option." But estrogen-only therapy should not be prescribed indiscriminately, she added.

"This applies only to women who have severe menopausal symptoms. We are not saying that we should give women estrogen to reduce the risk of breast cancer," Bernik added.

SOURCES: Lila Nachtigall, M.D., professor, obstetrics and gynecology, NYU Langone Medical Center, New York City; Garnet Anderson, Ph.D., principal investigator, Women's Health Initiative Clinical Coordinating Center, Fred Hutchinson Cancer Research Center, Seattle; Stephanie Bernik, M.D., chief, surgical oncology, Lenox Hill Hospital, New York City; March 7, 2012, The Lancet Oncology, online