BREAKING NEWS: STUDY SHOWS BREAST CANCER RISK FOR WOMEN USING HRT

Feb. 2000

Do you need to worry if you're using progesterone?

I've always suspected that my newsletter readers are pretty bright and this was dramatically confirmed recently, after the Journal of the American Medical Association (JAMA) published a huge study that examined more than 46,000 women, and which seems to show that the conventional medical HRT (hormone replacement therapy) regimen of Premarin and Provera confers a higher risk of breast cancer than estrogen alone. The study received a lot of media attention, most of it shamefully misleading.

Although my phone was ringing off the hook for days, and I received dozens of letters, faxes and e-mails about the study, the vast majority of you simply wanted to confirm that the study was looking at synthetic progestins and not at natural progesterone - as indeed it was. In other words, you folks are well aware of the difference between the synthetic progestins used in that study, and the natural progesterone that I recommend.

That's more than I can say for the media. It's terrific to know that my readers are more savvy than most of the medical writers and TV commentators in this country! I am amazed and disheartened that the newspapers and other media reported so inaccurately on this study, and used the term "progesterone" to describe the progestins used in the study. Now, if we could only educate them.

I encourage you to send letters, e-mails and faxes to point out this difference to any of the media outlets that you regularly use. And I also give credit to the authors of the study (Catherine Schairer et al) for using the term progestin throughout most of the study.

Many of you asked for my analysis of this JAMA study, so let's take a closer look at it.

HRT AND BREAST CANCER DEJA VU

Now maybe doctors will listen.

The January 26, 2000 issue of JAMA published the study "Menopausal Estrogen and Estrogen-Progestin Replacement Therapy and Breast Cancer Risk." The study's results show that women on HRT using estrogen and a synthetic progestin (not progesterone) have a breast cancer risk higher than that of women using estrogen alone.

Compared to no hormone use, the risk of breast cancer in women who use estrogen alone (ERT) is increased by one percent per year of use, whereas the risk in women using both estrogen and a progestin (HRT) is increased by 8 percent per year. This means that a woman on conventional HRT for five years has a 40 percent higher risk of breast cancer than a woman not using HRT. This is a huge increase.

The curious thing is that this has been reported several times in excellent studies over the past decade and only now has it made the news. Bergkvist (Sweden) reported it in 1989, and Willett, Colditz, and Stampfer found it in their Harvard Nurses Questionnaire study in 1995. Perhaps now it will sink into the minds of practicing physicians who prescribe these HRT concoctions.

The important thing to keep in mind is that progestins are not progesterone. Progesterone protects against breast cancer. Progestins are synthetic drugs that supposedly mimic real progesterone but in fact do not. As we have reported numerous times, there are many studies that show the difference between progesterone and the synthetic progestins, and, in particular, their differing effect on breast cells.

Since it is well established that excess estrogen can cause and promote breast cancer, why is the HRT combination worse than estrogen alone? I believe it's because progestins occupy progesterone receptors more tenaciously than progesterone, and thereby block progesterone from its functions, one of which is essentially to reverse estrogen's cancer-causing effects. Progestins convey different messages to target cells than real progesterone. Real progesterone activates gene p53 that slows breast cell proliferation and increases protective apoptosis (programmed cell death) whereas most progestins do not.

The message is simple. Unopposed estrogen is dangerous and estrogen combined with synthetic progestins is even more dangerous in terms of breast cancer risk.

To those of our readers who are using real progesterone, do not panic; real (natural) progesterone protects your breasts. Cowan et al from Johns Hopkins reported 1981 that premenopausal women with progesterone deficiency are 5.4 times more likely to develop breast cancer than women with normal progesterone levels. The recent study is just another confirmation that synthetic progestins should not be used.

Some doctors commenting on this recent JAMA study have suggested that women and their doctors should interpret this data to mean that they should use only estrogen for a few years at menopause. Since it is widely known that unopposed estrogen causes endometrial cancer, blood clots in the veins, and strokes, what are these doctors thinking? And futhermore, estrogen alone has also been proven to raise the risk of breast cancer-just not as much. This study should be interpreted as a clarion call to doctors to stop using progestins and start using progesterone. With all we now know about progestins-they increase the risk of cancer and heart disease (see the April, May and June 98 issues of this newsletter for details)- prescribing a progestin to a menopausal woman should be considered medical malpractice.

It would also be prudent to give serious thought to how safe it is to take the progestins found in birth control pills. Depo Provera, a long-term injectable form of birth control, is medroxyprogesterone acetate, the same progestin used in HRT. We already know Depo Provera causes devastating side effects in many women, and there are no long term studies of its effect on breast cancer risk. I can't think of a stronger indication than this present study to stay away from Depo Provera and reconsider oral contraceptives.

About 6,000 women were excluded from consideration in this study because they were using "shots, patches or creams." I suspect that means women who weren't using Premarin and Provera were excluded, but I also suspect there were many women in that group using transdermal and oral natural progesterone. I'm working on finding out if there's any data on the occurrence of breast cancer in these women.

I believe that progesterone is a potent protector against the 80 percent of breast cancer that is hormone-related. (See the April and May 98 issues of this newsletter for details.) My colleagues and I have asked thousands of women the following question: "Of all the women you know who got breast cancer, how many were using natural progesterone cream?" Except for a handful who by coincidence (or intuition) started using it a few weeks or months before their diagnosis, we haven't found any. I would like to pose the same question to you. If you know of a woman using progesterone cream who has gotten breast cancer, please e-mail me at info@johnleemd.com or send a letter to P.O. Box 3527, Santa Barbara, CA 93130.

I have clearly outlined the differences between progesterone and progestins in my books, but sometimes the Socratic method of questioning works better to illuminate an issue. I suggest that those who still insist that progestins and progesterone are the same, or that progesterone is a generic term that also covers progestins, ponder the following questions. If progesterone and progestins are the same:

• Why do fertility doctors always use progesterone and not progestins?

• Why do progestins cause birth defects, while progesterone is essential for a viable and health pregnancy?

• Why don't synthetic progestins show up in blood and saliva tests of progesterone levels? In other words, why doesn't taking a progestin raise progesterone levels in the body?

• Pregnant women are making 300 mg of progesterone daily in the last trimester. Why don't they have higher rates of breast cancer, as women do who use progestins?

• Why doesn't natural progesterone cause the side effects listed for medroxyprogesterone acetate (Provera) the most commonly used synthetic progestin for HRT?