Gene Screens May Reveal Future Illnesses - Or Spur False Hopes

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Web resources:

• "Uncertainties in Genetic Testing for Chronic Disease," by H. Gilbert Welch and Wylie Burke (PDF, 60K)

AMBI: country music

Hairdresser Heidi Jewell likes to work to the tunes of her favorite country music station.

She co-owns Generations Salon in Concord.

AMBI: snip snip chat and music.

You wouldn't know by looking at the 35-year-old Jewell that she's endured 27 weeks of chemotherapy and a few major surgeries.

“I mean we have so much cancer on my dad's side I always used to joke and say I'm going to get cancer someday it's just a matter of what kind and when.”

It all started during a routine visit at Concord Hospital.

After asking about her family's history with cancer, Jewell’s doctor ordered a mammogram.

And that x-ray revealed a 7 millimeter tumor in one breast.

“I was lucky that they found the breast cancer cuz like I said there was no lump no symptoms no indication at all. So I was just lucky……..and by the time I would have had a lump that I could feel I mean I already had four out of seven lymph nodes involved.”

Then Jewell had her DNA screened,.

And she found she tested positive for one of the so-called “breast cancer” markers - BRCA.

They are also linked to ovarian cancer.

Jewell didn’t want to fool around.

“So it really wasn't a question for me at 35 years old with two young children. Once I tested positive for that gene it was a bilateral mastectomy, hysterectomy. You know, get everything out that could possibly carry cancer.”

And while that may sound drastic, post-surgical biopsies revealed cancer in her other breast.

One of Jewell’s oncologists is Dr. Fred Briccetti.

His practice, New Hampshire Oncology and Hematology, partners with Concord Hospital in the genetic counseling program.

Bricetti emphasizes that the program won’t test just anyone.

The breast cancer marker is rare.

But it is found in about 5% of those who have had breast cancer.

So before recommending a gene test, Bricetti’s practice first screens patients for prior cancers and family histories.

“But if you carry one of the BRCA genes, your risk lifetime for developing a breast cancer may be 80% - that’s eight-zero % - and your risk for ovarian cancer may be as high as 20-40%.”

Bricetti added that both cancers tend to show up in younger patients if they carry the gene than if they don’t.

So while a gene test may provide valuable information, it can also mean a patient has to make tough choices at a young age.

And sometimes just having statistical information doesn't make decisions any clearer.

Gilbert Welch is a professor at Dartmouth Medical School.

He has serious doubts about the value of these $3000 dollar genetic tests.

He believes they can cause over-reactions … and under-reactions.

“In other words even if a gene tells you are at double the risk for developing say esophageal cancer. Uhm that's going from a very rare disease to a still rare disease. It’s going from 1 per million to 2 per million.”

And negative results, he says, can lead to false hope.

“The classic example is the test for the breast cancer gene. If you take that test and do not have the gene it turns out your risk for breast cancer is just about average so just because you don't have the gene doesn't mean you're no longer at risk for breast cancer.”

Welch is more concerned about testing for what he calls “weak genetic links.”

“But we all have alterations in our genome some which will have weak relationships with disease. Some of us may be at 20% increased risk for Alzheimer's, but 30% decreased risk for osteoporosis and maybe 50% increased risk of brain cancer but 50% decreased risk for esophageal carcinoma and the question is what are we going to do about all these small changes in risks.”

He adds that testing for the diseases themselves is most often a better way to go.

And that a patient’s medical history, lifestyle and family history often reveal enough information without genetic testing.

And Dr. Brecetti, with New Hampshire Oncology and Hematology agrees gene testing isn’t for everyone.

But for Hairdresser Heidi Jewell ……… the test was worth it.

“I mean I guess if I never knew about genetic testing, I probably would have just went and had a single mastectomy when the cancer was found and gone on with my life.”

But Jewell has no regrets about her choices.

Her biggest concern is for her children.

They have a 50-50 chance of carrying the same genetic markers.

For NHPR News, I'm Dianne Finch