Breast Cancer Speculations

Another breast cancer victory was declared last week. Speculation presented as fact was headlined on the front page of many newspapers last week. The New York Times headline read “Reversing Trend, Big Drop is Seen in Breast Cancer.” The researchers who reported this study at the 29th Annual San Antonio Breast Cancer Symposium attribute this “big drop” to women going off hormone replacement therapy (HRT). And the reason women went off HRT, these researchers state, is the reaction to the Women’s Health Initiative study that was cut short because women on HRT were showing a greater risk of breast cancer.

The message that most people will take away from this announcement is that hormones therapy puts you at greater risk of breast cancer.

That message is wrong.

Let’s start with the “big drop.” On average, the incidence of breast cancer dropped 7 percent from 2001 to 2003. The incidence among women between 50 and 70 dropped 12 percent during the same period. These are not nothing, particularly in light of the steady increase in breast cancer diagnoses over the last three decades, but “significant decline” might be more accurate than “big drop.” It is likely that “temporary, although significant decline” might be even more accurate.

Buried in the press release announcing the study but not in the Times article, the researchers point out that going off HRT likely affected the development of existing cancers. That’s because the type of cancer that decreased is called estrogen-positive meaning that the cancer cells have estrogen receptors so that estrogen stimulates cancer cell division. The pharmaceutical used in HRT consists of molecular imitations estrogen and progesterone.

So it makes perfect sense that by reducing exposure to a drug that promotes cancer cell proliferation would reduce breast cancer incidence. But that drug is not the same as bioidentical estrogen and progesterone, molecules that match the estrogen and progesterone a woman’s body produces naturally. And those bioidentical hormones have never been shown to be provocative when they are in balance.

Layna has discussed these issues many times on this show, both her own shows and her shows with John Lee and David Zava.

Because there is no published report of this study, all I have to work with is the newspaper article and the press release. None of these mention the racial differences in breast cancer statistics. When I look at the raw statistics from the National Cancer Institute (NCI), what I see is a decline in breast cancer among white women and no change for African-American women. How does this speculation about HRT explain that difference?

Addressing that question would dampen the celebration by introducing environmental factors into the mix, environmental factors that include exposure to carcinogens and social inequity (which includes the persistent, unequal treatment of African-Americans in the medical system).

But that’s not the message. The message is about, as the headline says, the “Reversing Trend.” Again, the raw NCI data don’t support that conclusion. It looks more to me as though the steady, upward trend has leveled off with help from this short term, small but significant downturn enjoyed by white women.

With so much wrong with this study, why would it get the prominence it did in the media? Because it delivered a message. The message is that hormone therapy causes breast cancer. That is wrong. It’s wrong because researchers are asking the wrong questions. They’re asking the wrong questions because they don’t know the difference between a drug that mimics sex hormones and molecules that are identical to what a woman’s body produces.