From the Executive Director: Of Pills, Prevention, and Politics

News and Views from the San Antonio Breast Cancer Symposium

by Barbara A. Brenner

People who have read my previous reports on the San Antonio Breast Cancer Symposium know that one of my pet peeves is the absence of much serious discussion on true breast cancer prevention. So imagine my surprise—and, in all honesty, skepticism—when a presentation was entitled “A Sharp Decrease in Breast Cancer Incidence in the United States in 2003.” Many people showed up for that presentation, including myself. And, my skepticism notwithstanding, I was not disappointed.

As Jane Zones reported for BCA from the conference, the data presented showed that, between 2002 and 2003, the incidence of breast cancer dropped by 7 percent. The decline was seen only in estrogen-receptor-positive cases of breast cancer among women 50 years old or older. Most of the presentation was focused on trying to explain why this decline occurred, and all of the speculation focused on the fact that in 2002 the Women’s Health Initiative results were released, showing an increased risk of breast cancer from hormone replacement therapy (HRT). Following that, women stopped taking HRT in droves. Breast cancer rates also went down during that time. The conclusion that many researchers have drawn is that the two are causally related.

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As Jane’s write-up of the presentation describes, there are lots of reasons to think that the conclusion about HRT is right, but the following questions are still unanswered:

  • If the decline is the result of the drop in HRT use, what is it about the biology of breast cancer and its relationship to hormones that explains that the drop showed up so fast in the incidence data?
  • Will the decline continue?
  • Is it premature to put so much emphasis on one explanatory factor so quickly? Should we wait to see what impact, if any, the decline in HRT use has on mortality rates as well as incidence?
  • If the downward incidence trend continues, would the HRT theory still make sense? How many years should we expect the HRT effect to continue?
  • What about the impact of other estrogens—the chemicals circulating in the environment that mimic the hormone in our bodies—on breast cancer incidence? Would the decline in incidence be even greater if we reduced our exposure to these?
  • How do environmental estrogens and synthetic hormones like HRT interact with the natural estrogen in our bodies?
  • Might any of the decline be the result of lower dosages of radiation in more modern mammography technology?
  • A lot of people—including folks here at BCA—are trying to figure out the answers. We’ll keep you posted.

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In the meantime, we were also treated at the symposium to a series of talks on chemoprevention—the idea that we can use pills to prevent diseases like breast cancer. The central presentation was from Leslie Ford, acting associate director for clinical research in NCI’s Division of Cancer Prevention. Ford’s entire presentation was on the effectiveness of drugs like tamoxifen and raloxifene in “preventing” breast cancer. I won’t rehash here BCA’s many concerns about this approach, but I do encourage readers to take a look at our newly revised policy on pills for the prevention of breast cancer.

Thinking about the 2003 incidence report after listening to Ford’s view of breast cancer “prevention,” I was delighted to read a New York Times editorial about the drop in breast cancer cases that urged a greater focus on prevention because there is still too much breast cancer around.2 I took the opportunity to send the following letter to the Times, which was published on December 25:

The news about the drop in breast cancer rates in 2003 is exciting for everyone, particularly if the trend continues in following years. It also underscores the fact that sometimes less truly is more, when it comes to disease prevention.

If analysis confirms the theory—linking less hormone replacement therapy to lower breast cancer incidence—this should change the way we think about disease prevention.

This is especially true as the National Cancer Institute and other cancer agencies look to advance chemoprevention (taking a pill to reduce the risk of the disease) of breast cancer.

As with hormone replacement therapy, any drug touted as a wonder is sure to eventually reveal a host of side effects. We will all be better off if we focus on avenues of prevention that take things out of our environment, rather than adding things to it.

The other thing that Ford talked about in her presentation was the next breast cancer prevention trial that the NCI is now gearing up for. The National Surgical Adjuvant Breast and Bowel Project will administer the trial. This trial, called STELLAR (as in “stellar mistake”), will randomly assign healthy women to receive either raloxifene (based on the STAR trial)3 or letrozole (an aromatase inhibitor) for five years. Since BCA began asking women with breast cancer about the side effects they have been experiencing on aromatase inhibitors (AIs), including letrozole (trade name Femara), we have learned a lot about some of the early side effects of these very powerful drugs (see our AI Side Effects Report). It is hard to imagine how a responsible agency, particularly one like the NCI, whose purpose is to keep people healthy, can even imagine encouraging healthy women to take an AI.

In the months ahead, BCA will actively discourage women from enrolling in trials like STELLAR and encourage them instead to work toward true breast cancer prevention—the kind that keeps you healthy, instead of giving you some other diseases you didn’t bargain for.

By the time next year’s San Antonio Breast Cancer Symposium comes around, we should be able to tell how effective we’ve been with our message.

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(As we prepared this issue of the BCA Source to go to print, a USA Today article indicated that proposed budget cuts to the NCI may result in the STELLAR trial being placed on hold.)4

1 See Jane Zones’s SABCS day one reflections online

2 “A Big Drop in Breast Cancer,” New York Times, December 16, 2006.

3 Read Jane Zones’s article “Pushing Raloxifene: Reports from the STAR Trial” in BCA Newsletter #92, August/September 2006

4 Liz Szabo, “Proposal Would Cut Cancer Institute Budget Again,“ USA Today, January 29, 2007.

Take Action: Help spread the word about the dangers of pills for the prevention of breast cancer. Send this article and BCA’s policy statement to all of the women you care about. Send a message to Leslie Ford at the NCI urging the agency to focus on research on true prevention of breast cancer, rather than treating healthy women with powerful pills.

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