BREAST CANCER GENE TESTING
Reed Pence: Of all the genes known to cause cancer, none are more well known or
feared than the so-called breast cancer genes, BRCA1 and 2. In most people, these
genes suppress the development of cancer. It's when they're mutated, and they don't
work as they should, that cancer is more likely--much more likely, according to Annette
Bar-Cohen, Executive Director Of The Center For Advocacy Training at the National
Breast Cancer Coalition.
Annette Bar-Cohen: So everybody carries these genes, but between 5 and 10 percent
of women (and some men as well) carry the mutation of the BRCA1 and 2 gene.
Charis Eng: BRCA1 and 2 mutations confine up to 85 percent lifetime risk of female
breast cancer, compared to 13 percent in the general population, in the West (I should
be careful to say that) and BRCA2 confirms a lifetime risk of male breast cancer of 10
percent, compared to .5 to one percent in the general population.
Pence: Dr. Charis Eng is Professor and Chair of the Genomic Medical Institute at the
Cleveland Clinic Lerner Research Institute. She says mutations in these two genes also
lead to a much higher risk of ovarian cancer.
Eng: Ovarian cancer is an up to 40 percent lifetime risk compared to risk in the general
population of .5 percent, so it’s quite a bit.
Pence: There are other genes that can also be involved in the development of breast
and ovarian cancer, but BRCA's role and risk are much more well known. So, it's no
wonder that when testing for BRCA1-and-2 became available, many women--especially
those with a family history of cancer--were interested. If the test comes back positive,
Bar-Cohen says the first step should always be the same.
Bar-Cohen: I think the first course of action that is really recommended is a
conversation with a genetic counselor, because this is a complicated issue. It has lots of
implications both for the woman and for her family, and so a really thoughtful an,
accredited and well-established genetic counselor is probably the first order of business.
And then there are various options that people have.
Eng: Women with BRCA1 and 2 mutations do benefit from increased surveillance of
breast screening, typically, with a breast MRI together with mammograms annually,
starting at 25, or 5 years before the youngest age of diagnosis in the family.
Pence: Many women consider a preventive double mastectomy to eliminate the risk of
breast cancer, as actress Angelina Jolie famously carried out in 2013 after testing
positive for BRCA1.
Bar-Cohen: They can consider that, and then hold off and wait for a while and see how
that happens, because we’re also talking about the risk of ovarian cancer, and so people
also consider whether they would think it’s important to have a oophorectomy--removal
of the ovaries--and of course the issue of reproductive health comes into play for women
who are in reproductive ages and still want to have a family.
Pence: Jolie also had her ovaries removed to prevent in her the disease that killed her
mother. Unfortunately, for ovarian cancer, that's one of the few alternatives. Women who
want children may have eggs extracted and frozen for future use before they have their
ovaries removed, but after a positive test, some women wonder if they should have
children at all, fearing the fate that they're leaving their daughters. So, testing is
important to many women, including some who haven't been able to get access to a test,
because the cost has been so high. It’s been $4,000 to start, and even fairly recently,
tests have cost $1,500 or more.
Bar-Cohen: Historically, we’ve also had a situation where there was one company that
had patented those genes, and it’s the only company that was able to actually do the
testing that was myriad. And, as of very recently, the courts have decided that that
patenting ownership is something that they were going to take away, and so this has
opened up testing for other labs and other groups. And, so, presumably we’re going to
see some reduction in the cost.
Eng: As time went on, the cost actually came down, and, more importantly, insurance,
almost all insurance, will pay for all or a good part of testing. So, suddenly, because
insurance got smart, this actually saves lives and in fact saves healthcare dollars. So,
quality of patient care goes up, cost goes down. Most of the party payers began to pay
for genetic testing, and importantly genetic counseling. Both must go together.
Pence: But it's not as if just anyone can be tested and insurance will pay for it. Testing
requires a prescription, and doctors usually look for a family history of breast cancer or
other red flags before they write one.
Eng: Lets say a person is in fact adopted, so essentially has no family history, this
person doesn’t know. Lets say it’s a person who is a thirty five year old female who was
diagnosed with breast cancer last year. So, young age of onset is a red flag, and in
many companies they will follow the NCCN National Comprehensive Cancer Center
network criteria, and so a young age of onset is a criterion for BRCA1 and 2 counseling
and testing. And often that might be the first person in the family to get a cancer, and in
fact that is the most informative person to start testing. So, let’s pretend you have no
family history at all, and you want testing. So, that’s population screening--and thats of
course rubbish, because the probability of finding a mutation is so low that it’s not good
practice of medicine--so often you want to start with someone who is affected, so people
who have come to me who are not affected, with a family history, we will take the one
that has the reddest of the red flags.
Pence: In that case, genetic testing isn't just about the benefit of the woman being
tested. It's for the benefit of the rest of the family--the sisters and daughters who haven't
yet been diagnosed and want to know how much they have to worry.
Eng: When the actual mutation is known, the other family members were not affected,
you can just look at that one spot as opposed to two big genes, and that’s called
predictive testing. It’s unfortunate that what we call the pro ban or the index case had to
have breast cancer first, but that’s pretty common.
Pence: But do women really have to wait for a family history? Some experts say that
leaves many women untested who nonetheless have inherited mutations--and their risk--
from their fathers. Those who advocate testing all women now may have a vehicle to do
it-- a new test for BRCA1 and 2 and 17 other genes linked to cancer that costs just $249
dollars. But Bar-Cohen and Eng say the new test doesn't change anything.
Bar-Cohen: The fact that this new Color Genomics test has come out and at this $249
rate does not change the biology of the BRCA1 and 2 mutations for women. And so it
doesn’t really broaden the criteria for who should get tested. It does offer a greater
access to testing, but we have to look at this testing and see whether actually this has
passed muster, whether we need more information about what this test is going to be
giving us. So, there are lots of questions that the test in fact raises, and it may in fact end
up broadening the pool, but we’re very cautious about that, and we think this needs a
great deal more consideration and discussion and more research.
Eng: You shouldn’t test everyone, because that is very bad medicine, and this test is so
cheap from a new company that I would not trust it at all. If someone walked in, I would
like to retest the person in a lab that is very, very experienced in this-- why? Because the
interpretation of the variant or mutation is dependent on the lab’s databases. Also, I have
a feeling that for that price, so this is not just BRCA1 and 2 testing, it’s a panel of breast
cancer associated genes, and for that price, I suspect, they’re using next generation
sequencing. It’s not the same as Sanger sequencing. So next gen sequencing, if you
don’t re-sequence lots and lots and lots of times, there are lots of false positives and
false negative--especially false negatives. So that’s very worrisome.
Pence: Bar-Cohen says the test may ultimately prove reliable, but she'd like to see
studies on it in a peer-reviewed journal. The developer of the test, Color Genomics, says
they're on the way. But even then, Bar-Cohen says the value of looking at so many
possible cancer genes is unknown.
Bar-Cohen: They are looking at an array of 19 related genes and 17 additional ones to
the BRCA1 and 2. And some of these genes for ovarian cancer and breast cancer don’t
have very much research behind them. And so we may see some variations and
mutations that emerge from the results of this test for these additional genes, but it’s
very, very complicated to understand whether in fact this information means very much,
and to what extent it really heightens and increases the risk for breast cancer and
ovarian cancer, should someone have several of these increased proportions. So, this is
a worrisome to some extent development until we have much more information.
Pence: Bar-Cohen says if backers of the Color Genomics test can show that it's valid, its
cheaper cost will be a positive development, but she still doesn't think every woman
should be tested.
Bar-Cohen: At this point, I do not think and the National Breast Cancer Coalition does
not believe that this is a warranted recommendation. The proportion of people as I said
it’s 5 to 10 percent of breast cancers that may be explained by the BRCA1 and 2 gene,
and to test every woman in the world age 30 and over really has no basis and would
really result in enormous numbers of women considering drastic measures to remove
their healthy body parts, when we really don’t understand all the information that would
be coming from these tests. And it would be an extreme thing to do.
Pence: What's more, were every woman tested, there wouldn't be enough genetic
counselors to go around. There's already a shortfall.
Eng: So demand will go up more, and supplies will be fixed, and be slowly increasing.
It’s very interesting, but the genetics professionals have always been vital, but the
realization that they’re even more vital is just sort of creeping into the consciousness of
medical centers and community hospitals throughout. And I think many of them are
going to say we can’t even hire anyone because it just snapped up.
Pence: Without enough genetic counselors to go around, Bar-Cohen says the result
could be disastrous.
Bar-Cohen: People who don’t get counseling are not prepared for the impact of what
they may get in terms of the results. The other shortage that we have, I think, is in
adequate training for frontline family physicians and internists and so on who are, in the
end, the people who are providing the results of these tests and to what extent are they
all adequately trained in the latest research and in the nuances of being able to have this
conversation with their patients, so women may get terribly frightened. It may be an
incredibly difficult thing to deal with. They may not understand what the implications are.
Women who have daughters will be very concerned, and this may impact questions of
raising a family of the issues around if there are men involved in the family history and
so on. And it can be very difficult if you don’t have a trained person navigating you
through.
Pence: It may be that someday, maybe even in the not-so-distant future, many more
women will be tested for breast cancer genes. The cheaper test may make it possible.
But for many experts, the test is simply too new, and the answers it provides are far too
important for it to carry any doubt. You can find out more about all of our guests on our
website radiohealthjournal.net, where you can also find archives of our segments. You
can also find our shows on iTunes and Stitcher. I'm Reed Pence.