Last month, researchers reported that breast cancer incidence rates in the U.S. fell dramatically between August 2002 and December 2003. Some have speculated the drop occurred because millions of women had stopped hormone treatments after a large national study in 2002 concluded that combined hormone-replacement therapy increased breast-cancer risk.


Doctors here, however, caution women against relying on the recently released statistics as a reason to stop hormone therapy, and say they should consult their physician first.


We have worried women calling in, and they deserve to know accurate information, not get little sound bites and get scared to death, says Dr. Steve Brisbois, of Northwest OB/GYN PS. The study is reporting an incidence of breast cancer, and anything beyond that is speculation.


Doctors say that while the drop in breast cancer incidence is significant and deserves further study, it doesnt prove that hormone-replacement drugs cause breast cancer. Nonetheless, they say more women in recent years either have been abandoning hormone-replacement therapy altogether or are turning to bio-identical hormone-replacement therapy. Women who are taking such therapy as an alternative treatment werent included in the 2002 study.


In the summer of 2002, the federal government halted part of a major study on hormone-replacement therapy, saying a common combination of drugs used in the study to ease the symptoms of menopause and possibly protect against heart disease and osteoporosis was associated with a higher risk of breast cancer, heart attacks, strokes, and blood clots. That year, as many as a third of American women over age 50 were taking menopausal hormones.


The following year, the overall incidence of breast cancer declined by 7 percent, or about 14,000 cases, marking the first time breast-cancer incidence had fallen significantly after they had risen steadily every year since 1945. For women with whats called estrogen positive tumors, which account for 70 percent of all breast cancers, rates fell 15 percent in 2003. In women ages 50 to 69, the group most likely to be taking hormones for menopause, the incidence of all breast cancers fell 12 percent that year.


We dont want people who need hormones to panic, but at the same time, we want people to be aware of the potential side effects of taking them, says Dr. Carol Guthrie, of the Spokane Breast Center clinic. Theres a tendency in the public where anybody who takes hormones and gets breast cancer blames the drug or blames themselves, when the majority of women would have gotten it anyway.


The medical community has known for some time that hormones act like a fertilizer to fuel the growth of estrogen positive tumors, but no one knows what causes the tumors to form in the first place, Guthrie says. The theory is that once women stopped taking hormones in 2002, the tiny tumors that were present in their breasts were deprived of estrogen and thus grew more slowly, making them too small to show up on mammograms, she says. Cancers typically take two to five years from the time a cell mutates before they appear on mammograms, she says. In the next few years, as the tumors grow large enough to be detected, Guthrie expects that breast cancer rates probably will spike.


Its possible that the new data reflects true decreases in cancer, she says. But, this study appears really dramatic, and anytime you have a huge difference thats unexpected, you have to ask, Is this real?


Brisbois says hes waiting to see if the drop in breast-cancer incidence was an anomaly or if it becomes a long-term trend. He says some of his patients have stopped taking hormones after being frightened by the recent studies, and their quality of life has diminished as a result. Many of his patients, though, have considered the potential risks and are continuing their hormone treatments.


Theres a lot of women who function at very high levels and during menopause hormones help them to continue to function at those levels, Brisbois says. The catch is that theyre worried to death theyll develop cancer, and they have to balance the risks and benefits.


The ideal hormone-replacement therapy would be part of a category of hormones called selective-estrogen receptor modulators (SERMs), which block the action of estrogen in the breast and other tissues by occupying estrogen receptors inside cells, he says. Unfortunately, SERMs already on the market, such as Tamoxifen, which are used to treat women with breast cancer or who are at high-risk for breast cancer tend to aggravate menopausal symptoms, he says. Drug companies have been researching SERMs that have positive effects on breast tissue, bones, and menopausal symptoms, but a drug that would accomplish those objectives is probably years away from reaching the market, he says.


That would be the best of all worlds to help with menopause symptoms, protect bones, and decrease the risk of breast cancer, Brisbois says.


Dr. Cheryle Hart, a gynecologist here who prescribes bio-identical hormones, through her Wellness Workshop, says she also is looking forward to the development of an SERM that can treat the symptoms of menopause effectively. She expects researchers will focus more of their efforts on developing such a drug in the future, as increasing numbers of women look for alternatives to conventional hormone-replacement therapies currently on the market.


The women I see are choosing to read more about their options, have their hormone levels measured, and take bio-identicals, Hart says.


Bio-identicals


Bio-identical hormones are made from substances that are taken from plants and processed in a laboratory to produce a pure hormone that has the same molecular structure as a human hormone. They almost always are compounded in specific combinations and doses for each patient.


Cathy Hudek, director of pharmacy at Riverpoint Pharmacy, a Spokane company that compounds bio-identicals, says demand has been rising for such treatments. Hudek says doctors also are becoming more willing to prescribe bio-identical hormones or at least discuss them as an option with their patients.


Ive seen a huge increase in women who are seeking bio-identicals as an alternative, Hudek says. Most women who are interested have done some reading and want to get more information or have been referred here by their doctor.


Dr. Stephanie Moline, of Cancer Care Northwest PS, agrees that bio-identical hormone-therapy has become more popular with women here in recent years, but she cautions that studies to show whether such treatments are better or safer than conventional therapies havent been concluded yet.


If a woman has breast cancer, her doctor will advise that she stop taking hormones of any kind, Moline says.


Meanwhile, Moline says she also has seen women who dont have cancer but have pre-cancerous or fibroid tumors and are more cautious about taking hormones for menopause than in years past. Although the drop in breast-cancer incidence rates in 2003 doesnt prove that hormones cause breast cancer, it is important information for women to bear in mind when deciding whether to undergo hormone-replacement therapy, she says. She advises menopausal women who arent suffering from any symptoms against taking hormone therapies.


Its an important trend and certainly bears watching, but there are several reasons why different women have different cancers at different times in their life, Moline says. The biggest risk factors are being female, having breasts, and your age.


Breast cancer is the second-leading cancer killer of American women. One in eight women who reach the age of 90 will get breast cancer, Moline says. An estimated 200,000 women will be diagnosed with breast cancer this year, and 40,000 will die from it, she says.


Contact Emily Brandler at (509) 344-1265 or via e-mail at emilyb@spokanejournal.com.