Genetic testing a plus, not a fail-safe

Oct. 14--Boise'sGlenna Tooman thought she'd get the news this year that she carries a hereditary link to breast cancer.

Instead, her family's story shows how far genetic testing still has to go before it can flag more cases of breast cancer before they start.

Tooman's mother died of breast cancer when Tooman was a child. Tooman's sister had breast cancer twice. Tooman, a wedding and event planner, survived early-stage breast cancer in 1992.

When she got a call from a health care provider early this year, letting her know that her insurance plan now covers a wide range of genetic testing for breast cancer, she jumped at the opportunity. Genetic testing can help family members better learn, early on, whether they're at high risk for breast cancer.

Glenna had 23 genes tested, including the well-known BRCA1 and BRCA2, in April. Because genetic testing is built into the Affordable Care Act's changes to health insurance and in some cases is now considered preventive care, many plans now cover it, including Tooman's.

If her results came back positive, it would start a chain of testing down through three generations.

"This holds huge implications for our family -- not only for the women in the family, but also for our sons, who may be at increased risk for several forms of cancer," Tooman wrote in June. "Because of changes in insurance coverage, my sister, my niece and I will pay nothing for the testing. The fact that many insurance plans now cover genetic testing is still largely unknown to most women, as is the fact that many more genes can be tested."

In July, she got the results: negative.

That doesn't mean Tooman's family carries no hereditary predisposition for breast cancer. It just means they don't have a hereditary link to breast cancer in the genes currently being tested.

If "undiscovered genetic mutation" sounds rare, it's not.

"We're estimating about 20 to 25 percent of families who have tested negative on BRCA have some other gene" that is tied to cancer risk, said Jennifer Eichmeyer, Tooman's genetic counselor at the Mountain States Tumor Institute. "We don't test all 25,000 genes (humans have, and) up until recently, we only tested two or maybe five."

Of the roughly 2,600 breast-cancer patients Eichmeyer has seen in the past 10 years, only about 13 percent tested positive for a hereditary link to breast cancer.

Tooman and her family members could help advance medicine by joining gene-discovery research studies, Eichmeyer said. The only hitch is that studies require four living relatives with breast cancer, and the death of Tooman's mother left only three. Besides Tooman and her sister is Tooman's niece, 45-year-old Paula Portz, who received her diagnosis Aug. 28.

Portz lives in Iowa but grew up in Mountain Home. She said learning she had breast cancer scared her. She went in for a double mastectomy in late September, and her prognosis now is "very good," she said.

Portz has been tested for breast cancer genes. Her test, too, came back negative.

Eichmeyer said patients should not rely solely on the BRCA1 or BRCA2 test, which can give them a false sense of security if the test comes back negative. She recommends patients visit genetic counselors to find out whether there might be a hereditary link.

There are only five genetic counselors locally who specialize in cancer, Eichmeyer said. But that number is growing, she said.

Tooman's sister now has been tested, too. She'll find out in November whether she carries any of the hereditary links that researchers have identified.

Audrey Dutton: 377-6448, Twitter: @IDS_Audrey

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