Thursday, October 09, 2008

Gene testing for Breast Cancer: Hype or Hope?

WBP supporter and personable pundit Art Caplan explains in his most recent MSNBC column that biotechnology firms hope to cash in on women’s fear of the disease:

Fear of breast cancer has created a tempting market for companies to sell genetic testing directly to consumers. The disease kills 40,000 people a year in the U.S., with an estimated 212,920 new cases diagnosed in 2007, according to the Mayo Clinic.

It’s no wonder women would want a reliable gauge of their risk. However, American women should be aware that genetic tests for breast cancer are more hype than real hope.

On Wednesday the biotech research company Decode Genetics of Reykjavik, Iceland, announced it will sell a new test for $1,625 that it claims will allow women “to assess their personal risk for the common forms of breast cancer.”

Genetic testing for all sorts of conditions is all the rage these days. Everywhere you turn, some company is urging you to spit in a cup, take some blood or swab your cheek so your DNA can reveal your health risks, know who your long-dead ancestors are, pick the right mate or help you design a diet that is perfect for your genetic makeup. But, “spitomics” has gotten way ahead of genomics.

Sadly, the tests Decode and other companies are offering are more likely to empty family pocketbooks and leave women with a false sense of security than they are to prevent breast cancer. There is simply not enough federal and international regulation in place to determine which tests are accurate or how heredity interacts with lifestyle to create individual risks.

If the Food and Drug Administration and Congress do not rein in the corporate greed that is currently driving the sale of genetic tests for breast cancer and other diseases and conditions, we could soon have an industry that bears an uncanny resemblance to the home mortgage business.

Marketing for genetic tests is already ubiquitous. The television commercials and magazine ads, which ran in Denver, Atlanta and various cities in the Northeast, promise women that cancer does not have to be “inevitable." They also claim that the average woman can reduce her risk of developing cancer through genetic testing.

Myriad Genetics, the Salt Lake City biotechnology company behind the heavy ad push, charges about $3,000 for a complete risk-disposition test. Myriad, which holds a patent on the first breast cancer test, has been taking full advantage of the genetic testing monopoly it enjoyed until Wednesday when Decode entered the market with its new, more generalized test. To date, Myriad has been very tough about enforcing the patent, even though medical centers in the United States and other countries say they could do the same testing for a much lower cost.

Only small fraction would benefit
In reality, the numbers about detectable risk don’t really back up Myriad’s ad claims.

Of the more than 200,000 new breast cancer cases, only about 20,000 seem to be connected to the BRCA1 and BRCA2 genes — the genes most closely linked to the inherited form of the disease that Myriad’s test can detect. For women without a family history of the disease, perhaps 1 percent would benefit from the test.

On one hand, it would seem to make sense to seek out genetic testing to avoid becoming a breast cancer statistic. Or does it?

Contrary to the marketing messages, only women who have a strong family history of breast cancer — two or more parents, grandparents or siblings who have developed the disease — need to talk to their doctor or a genetic counselor about the value of any form of genetic testing.

Decode’s newer test is not really accurate enough or based on a large enough sample of women to accurately predict much about an individual woman’s chance of getting breast cancer.

If you are worried about your risk of getting the disease, or are thinking about getting a genetic test done for any other reason, talk with your doctor or a genetic counselor who can determine whether your family history justifies the expense. You may be surprised to find that you can make changes in lifestyle and monitoring your own health that can reduce your risk without testing.

The genetic revolution holds much promise for improving our health. Currently, profit and market advantage are playing the key roles in shaping how genetic testing is evolving. These are not the right navigation tools to help women at risk of breast cancer — or the rest of us — capture that promise.

Arthur Caplan, Ph.D., is director of the Center for Bioethics at the University of Pennsylvania.

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