Iskander: Hello I'm Dr. John Iskandar.
Welcome to CDCs Beyond the Data.
I'm here today with Dr. Lisa Richardson Director
of CDC's Division of Cancer Prevention and Control
and a practicing Oncologist.
Welcome Dr. Richardson.
Richardson: Thanks for having me, John.
Iskander: In past Grand Round sessions we've heard
about screening and other preventive measures to try
to decrease the population burden of cancer.
At today's session we learned about genetics
and its role specifically in certain types of cancers.
What do we know about the burden
of genetically determined cancers?
Richardson: We've known for a very long time that cancers run
in families as you probably know
and recently we've learned there're certain gene mutations
that can increase the risk for breast and ovarian cancer
as well as colorectal cancer which we learned about today.
Iskander: So what are some of the terms that people may hear
for those specific types of either genes or syndromes
that go with breast and ovarian and colorectal cancers that are,
have these genetic factors?
Richardson: Well for breast and ovarian cancer the genes
that are defective are the breast-cancer one
and breast cancer two genes.
They lead to an elevated risk of breast cancer and account
for about 25% of all breast cancers diagnosed
with a genetic syndrome.
For colon cancer's Lynch syndrome which is also a defect
in a gene that causes DNA not to be repaired and that occurs
in about 3 to 5% of all colon cancers.
Iskander: Okay, so there are clues to these
that clinicians can be aware of often in family history.
What are some of the interventions
on either an individual or population level
that can benefit people with these family
or genetic risk factors?
Richardson: Well the first thing for the doctor
or other healthcare provider to do is
to take a complete family history to determine the risk.
The histories of people who come to you and that you're trying
to figure out if they have a genetic mutation are cancers
occurring at early ages in family members.
For breast cancer it is bilateral breast cancer,
cancer before the age of 40.
For colorectal cancer the same.
The average age of colon cancer being found is about 60.
People less than 50 less than 40 would now be tested
for higher risk, to see if they have a higher risk
of a gene mutation.
Iskander: Okay, so that's how we identify people who are at risk.
There are ways to then enhance our ability to screen them
or detect issues early and what are some of the options there?
Richardson: So for breast
and ovarian cancer the main options are surgical,
where you would, we would recommend
that women have mastectomies or remove both breasts as well
as have their ovaries and fallopian tubes removed.
This will, this actually removes the tissue
that will become cancerous
and therefore the cancer would not develop.
For colorectal cancer is quite different
with Lynch syndrome we would start screening earlier,
as early as 25.
Usual recommendations to start at 50.
Iskander: So again we're tailoring these type
of screening or intervention recommendations
to people's genetic and family risk.
So, and, and again, I think we, we should stress that some
of the particularly surgical things are considered options
at this point rather than recommendations.
Richardson: So for breast and ovarian cancer
as well there are medical, you know, medical medicines
that we can use as well to lower the risk of developing a cancer.
Iskander: So, I think one of the insights
from today's session was that, we are now crossing the chasm,
if you will, from doing this on an individual level to looking
at this from a public health perspective and we,
we heard from Deb Dekat from the Michigan Department
of Health and Human Services.
What are some of the things that CDC is helping states do
to really implement a public health approach
to genetic cancer?
Richardson: So we have funded several states including
Michigan that presented today to try to get a handle
on what the true prevalence is
and what the true risk is in the population.
In Michigan in particular they work
with prop...uh...primary care providers
to actually raise their awareness and screen women
and men for these genetic syndromes and some of the data
that she presented today show that they have had some success
with increased numbers of referrals for screening as well
as increased testing for these gene, gene mutations as well.
Secondarily we've been using our Cancer surveillance data,
the cancer registries
to identify what might be the prevalence in the population
of people who need to be screened for a high risk
of familial cancer or hereditary cancers.
Iskander: Yes, so again, using a lot of the classic public,
public-health approaches of,
of surveillance educational interventions,
I believe they're also working on some,
some policy interventions as well.
So you, you did mention screening of,
of men could you just remind us what,
what can what familial cancer syndromes men might be at risk
for and what some of the family history markers
for that might be?
Richardson: Alright, so for men the main one is colorectal
cancer, men and women are affected at similar rates
with the gene mutations for Lynch syndrome.
In particular one signal versed on signaling families
of male breast cancer the BRCA2 mutation leads
to more male breast cancer and those men definitely need
to be evaluated as well as their family members need to know
that there is a man in the in the family
with breast cancer Iskander: So we heard today from,
from Lindsay, Lindsay Avner who is, runs a not-for-profit
that works on educating both patients and clinicians
about hereditary determined cancers.
She describes herself as a cancer previvor.
For people in our audience who are hearing that term
for the first time what does that mean?
Richardson: Well I believe a previvor,
the way the term was used by Lindsay, are people who know
that they have mutations in these genes,
who've taken actions to prevent a cancer and so
in Lindsay's case, she had a bilateral mastectomy
to prevent the cancer from ever happening.
And I think that's what that's what they mean
when they say previvor, never develop cancer.
Iskander: And I believe she was one of, really the first people,
to, to opt for this...
Richardson: Yes, yes.
For the best alternative.
Iskander: So we collaborated on the session with the office
of public-health genomics at CDC and,
and Dr. Muin Khoury gave a talk where he put this
in the broader context of,
of some new initiatives particularly precision medicine
so can you give us a little flavor how is what we're talking
about today, how is that an example of precision medicine?
Richardson So, my understanding of precision medicine is
that we're trying to as a research community,
we know of some gene mutations but some unknown.
So what we're trying to do is look at cancers and families
to determine where those gene mutations are
and determine what the significance is
of those mutations.
The secondary part of precision medicine is looking
at actual cancers to determine therapy.
But the one we're most interested in today is the one
where we look at the gene profile of a person to see
if we can determine risk for developing cancer in the future.
Iskander: So, let's, let's come,
come back to that more specific issue of,
of precision medicine right now to, to conclude,
so what are our goals as a as a public health community for the
for the near and may be less near-term future in terms
of detecting these on a population level what is
that future will look like to you?
Richardson: Well, as an oncologist I'm very excited
about the new precision medicine initiative, us discovering more
and more what causes cancer so that we can intervene
but the one thing I like for us to remember is
that the family history tool is the very first gene mutation
tool that we've developed and that we can use, and regardless
of what those results are when you have testing done,
if you have a strong family history it means something.
On a population level to go deeper into the genome look
for signals for genes that might be new to cause cancer
as I said earlier only about BRCA1 accounts for 25% or so
of hereditary breast cancers so there's a lot of things
that we don't know even about hereditary cancers
that we're able to test for
and that's why I think the new initiative will be helpful.
Iskander: Okay and you,
you mentioned the family history tool and there is a link in the,
in the presentation and we'll make sure
that that's available to people.
Thank you very much for joining us today Dr. Richardson.
Richardson: Thank you.
Iskander: Please join us next time for Beyond the Data.