Should screening for breast cancer gene be expanded?

Should screening for breast cancer gene be expanded?

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Breast cancer ribbon FILE PHOTO
Breast cancer ribbon FILE PHOTO

This is the second of a two-part series on genetic testing. Click here for part one.


Cancer researcher Kelly Metcalfe is unequivocal when asked what expanded testing for the gene linked to breast and ovarian cancer would mean for Jewish women.

“Do I think we could save lives if population-wide genetic testing was offered to all Jewish women, if they wish? Absolutely,” she says.

Currently, no country offers widespread screening for mutations in the BRCA gene, which is linked to a significantly higher risk of breast and ovarian cancer. In Canada, typically only women who meet specific criteria, including having a family history of cancer, are eligible for the genetic tests.

But research studies in Israel, England and Canada have concluded that making screening available to all Jewish women would save women’s lives and be cost effective, Metcalfe said.

READ: FIGHTING BREAST CANCER AT 28 YEARS OLD

The Canadian Cancer Society, which a few years ago had expressed reservations about expanded testing, is also increasingly convinced by the research.

“The Canadian Cancer Society encourages provincial and territorial health-care authorities to review their genetic testing guidelines and the evidence on the impact of expanding to Jewish women to ensure that the greatest number of people can benefit from these programs,” Dr. Robert Nuttall, assistant director, health policy, said in a written statement sent to The CJN.

It’s also important that genetic counselling be offered to help people understand the results and their options, Nuttall said.

Between one per cent and 2.5 per cent of Ashkenazi Jews, both men and women, carry a mutation that renders the BRCA gene less effective in preventing cancers. (For non-Jewish women about 1 in 500 carry a mutation.) Breast cancers attributed to the mutations tend to be more aggressive and occur in younger women.

A large-scale screening program at Toronto’s Women’s College Hospital that started in 2007 offered the test to all Jewish women, not only those with a family history of cancer. “It was absolute craziness. Women were trying to get at this test,” recalled Metcalfe, an adjunct scientist at the Women’s College Research Institute.

The research study, initially slated to test 2,000 women, added an additional 4,000 spots to accommodate the demand.

In a paper published in Current Oncology last summer, Metcalfe, the lead author, reported that 38 per cent of the women who tested positive for one of the three most common mutations had no family history that would have merited screening under the current guidelines.

The women’s reactions to learning they carried the mutation, often without any inkling of trouble beforehand, were rapid. Within one year of testing positive, all of the women had more intensive MRI breast screening. Within two years, 90 per cent had undergone a prophylactic oophorectomy (surgical removal of ovaries and fallopian tubes), which is recommended because ovarian cancer is notoriously hard to detect until it is quite advanced. The surgery also reduces the risk of breast cancer.

The more intensive breast screening also caught cancer in some women earlier than it would have otherwise been detected.

“We identified women that would never have been identified. Because those women were identified before they had cancer, they did something with the test information,” Metcalfe said in an interview. “I think we saved lives.”

Natalie Witkin was 30 when she learned she carried a BRCA mutation in 2000, just a few years after the genetic mutations were discovered by researchers in the United States and Canada. She was encouraged to be tested after a cousin developed breast cancer.

“Finding the mutation and learning about the mutation is a loss of innocence. It’s a piece of information you can’t unknow,” she said.

“I’m glad that I know. At first it was certainly very difficult to find out. It weighed on me for months,” she said.

Witkin did not know anyone outside her family in the same situation, and support groups only existed for people with a cancer diagnosis, not a genetic finding. It would be more than a decade before the most famous face of genetic testing, actor Angelina Jolie, would reveal that she, too, carried the faulty gene and had undergone a preventative mastectomy.

Witkin eventually started a support group for women like herself, and today, she’s the director of partnerships and programs at Willow, Breast and Hereditary Cancer Support.

“In the end, I felt empowered and lucky to be able to take control of the outcome,” she said.

“If I hadn’t known [about the BRCA mutation], I would have woken up in my 40s with advanced cancer and then have very limited choices. ”

The screening project at Women’s College Hospital has since concluded, and women who want the test but do not meet the criteria can arrange for it privately, at a cost of about $500, Metcalfe said.

The study also demonstrated that it would save not only lives but also money. Each test costs researchers about $100, so the cost of finding the one woman in a hundred who carries the mutation is about $10,000.

The cost of surgery, chemotherapy and hormonal therapy for a woman with breast or ovarian cancer exceeds that, Metcalfe said.

READ: CIJA AMONG GROUPS PUSHING FOR LAW AGAINST GENETIC DISCRIMINATION

Eventually, she would like genetic testing to be routine for Jewish men and women, since men who carry one of the BRCA mutations have a higher incidence of prostate and pancreatic cancer. A positive test for a man also has implications for his children, who may have inherited the mutation.

In the meantime, Metcalfe said it’s just a matter of time before the test is offered routinely to Jewish women.

“We need to take small steps, this isn’t trivial in terms of the cost. If we’re going to be lobbying the government to expand testing, the first step is probably to women.”