Why Breast Cancer Rates Dropped
by Virginia Hopkins
from the Virginia Hopkins Health Watch Vol 3, Issue 1
In November 2006, research was released by cancer centers around the U.S. showing that breast cancer rates have dropped dramatically since 2002. Most doctors and researchers agree that the drop was created when millions of women suddenly stopped using hormone replacement therapy (HRT) after the Women’s Health Initiative (WHI) study group announced, in the summer of 2002, that HRT users had an increased risk of breast cancer, stroke and heart disease. Estimates are that as many as 50 percent of women using HRT stopped taking it within six months after the WHI results came out.
How large was the drop in breast cancer? It depends on who’s reporting the statistics and how they’re interpreting the numbers. Most of the data came from the National Cancer Institute’s (NCI) cancer registry.
Here's How Dramatic It Is
- There was a 2.5 percent drop in breast cancer cases in 2002, and a 7 percent drop in 2003.
- If you just look at estrogen-driven cancers (the most common kind and the kind caused by HRT), in the months between August 2002 and December 2003, there was a 15 percent drop in breast cancer cases.
- If you just look at women between the ages of 50 to 69, when women are most likely to be using HRT, there was a 12 percent drop in breast cancer cases in 2003.
- A northern California group led by Kaiser and Stanford University combined their own numbers with the NCI numbers and reported a 10 to 11 percent drop in breast cancer cases between 2001 and 2003.
Preliminary numbers for 2004 show the decline is continuing. Suffice it to say that no matter which way you crunch the numbers, breast cancer rates have dropped significantly for the first time since 1945.
Thousands of Lives Saved
According to the American Cancer Society, in America, breast cancer is the most common major cancer in women. This amounts to about 200,000 cases of invasive breast cancer each year. If you do the math (these are very crude estimates, but it gives a sense of the magnitude of this decline), a 7 to 15 percent drop in breast cancer cases represents between 14,000 and 30,000 women a year who won’t be getting breast cancer.
When we look at breast cancer mortality (women who die from breast cancer), the numbers get a bit more muddled because women may die from the side effects of radiation and chemotherapy, but that may not be counted as dying from breast cancer. Most estimates are that 40 to 50 percent of women with invasive breast cancer die from it within 20 years. If we crunch the numbers again, at the current rate of decline, in one year between 5600 and 15,000 women’s lives will be saved. Wow!
Putting Out the Breast Cancer Fire
Most breast cancers take seven to ten years to develop from a few cells to a lump detectable by mammogram or breast exam. So how did this decline show up so quickly after the WHI results were announced? There is some evidence that adding conventional HRT (e.g. PremPro) to an already existing breast cancer can cause much more rapid growth, and some theories that it may stimulate otherwise “quiet” cancers to grow. In other words, adding PremPro to an already existing cancer may be like throwing gasoline on the fire.
I’d hazard an educated guess that in addition to the millions of women who dumped their PremPro, the decline is also related to the millions of women who have switched to natural hormones since the late 1990s and as a result have actually prevented breast cancer altogether.
Two large and well-done French studies following women for 9 to 20 years who were taking estradiol (a natural estrogen) and an oral progesterone, found no increased risk of breast cancer and in fact even a slight decrease in breast cancer in one.
Marin County Breast Cancer Cause is Found
Back in 2002 my friend and co-author, the late Dr. John Lee, was scheduled to give a talk in Marin County in Northern California near where he lived, an area with very high rates of breast cancer. In the December 2002 issue of the John R. Lee, M.D. Medical Letter he wrote, “ It’s the estrogen, stupid! That was my first reaction to a newspaper headline I read this morning: ‘Researchers say pollution not cause of Marin County breast cancer.’ No, it’s not the power lines, it’s not the styrofoam cup factory, and it’s not the quarry. It’s the estrogen!”
But of course at the time Dr. Lee got “no respect” from most of his colleagues on this insight, so I was tickled to read the following in a New York Times article (12/15/06) by Gina Kolata:
“The heaviest users of hormone therapy were women in affluent places like Marin County, where high breast cancer rates had long troubled women and researchers. Women in those areas also largely abandoned the treatment after the 2002 report and their cancer rates declined accordingly, Dr. Clarke said. Dr. Marcia Stefanick, a professor of medicine at Stanford University and chairwoman of the steering committee for the Women’s Health Initiative, said she found the hormone argument persuasive and felt it helped clear up the mystery in Marin County. ‘Everyone kept saying, “What is it? What’s in the environment?” she said. Now, she said, it is becoming clear. ‘The best explanation is hormone therapy.’"
Does the connection between conventional HRT and breast cancer apply to natural hormones?
The best way to answer that is to again quote Dr. John Lee, in answer to that very question:
“Not at all. What I recommend is first measuring saliva hormone levels to find if there is a hormonal imbalance. Then, if necessary, correcting the imbalance using natural hormones in physiologic doses, which means ordinary doses that the body would naturally produce itself. (Please read one of our "What You Doctor May Not Tell You..." books for details.)
Another way to look at this is, from puberty until menopause, a healthy woman’s body is making its own natural hormones in synchrony and balance, without giving her cancer, heart disease or strokes. What I recommend is attempting to regain this natural balance as closely as possible.
Conventional HRT not only fails to measure hormones and use physiologic doses, it uses synthetic, not-found-in-nature ‘hormones’ that are foreign to the human body and cause a long list of unwanted side effects.”
Data came from the American Cancer Society, the National Cancer Institute, the Centers for Disease Control, and the Journal of Clinical Oncology (Clarke et al, Vol 24, 33:Nov 20 2006)
de Lingnieres et al, Climacteric 2002
Fournier A et al, Int J Cancer 114:2005