Your genetic makeup - half from your mother and half from your father -
is responsible for your hair and eye color. Yet it’s more than curious
exploration of your family tree. Today, up to 15 percent of cancers are
tied to a hereditary link. Knowing about them may help you prevent or
reduce your risk of cancer.
February is National Cancer Prevention Month. To save lives, the experts
at Baptist Health’s
Lynn Cancer Institute and
Miami Cancer Institute would like to raise awareness of the value of
genetic assessment and
testing.
Scientists have identified many mutations that increase the risk for breast
and gynecologic cancers, colon cancer, some gastro-intestinal cancers,
kidney cancer and more. And because the field of genetics moves at a rapid
pace, discoveries may impact everything from guidelines for cancer screenings
to treatment options for those who have cancer.
Information is Key
“The more accurate our information, the better our guidance on prevention,” says
Louise Morrell, M.D., a cancer genetics specialist and medical director of Lynn Cancer Institute.
“In genetics, unlike other areas, the benefit extends to family
members and perhaps for generations to come.”
Researchers have worked for decades on uncovering the link between genetic
mutations and cancer, but public knowledge grew when actress Angelina
Jolie had her breasts removed in 2013, and then her ovaries in 2015, because
she carried the
BRCA1 gene mutation that is linked to a higher risk of breast and ovarian cancer. The same
BRCA1 and
BRCA2 mutations that raise the risk of breast cancer in women, also raise the
odds of breast cancer in men by eight times, according to the American
Cancer Society, and increase the chances of prostate cancer.
Ms. Jolie’s mother, grandmother and aunt had died from cancer, and
her decision to prophylactically remove her breasts, ovaries and fallopian
tubes to lower her cancer risk came after multiple tests and conversations
with experts. In addition to Ms. Jolie’s public sharing of her story,
technological advances have made it possible to test for more genes, sped
up testing and made it less expensive. The answers from genetic testing
can also help drive treatment and surgery decisions in someone already
diagnosed with cancer.
Where Your Genes Come From
It’s not only your mother’s history you must be aware of, however, says
Arelis Mártir-Negrόn, M.D.,
medical geneticist and head of the Clinical Genetics program at Miami
Cancer Institute. “As many men pass down mutations as women. That
means you should be as aware of your father’s family’s cancer
history as your mother’s. Know your family history. Ask questions.”
All people inherit two copies of each gene: one from their mother and one
from their father. Variations in genes are normal and are what give us
our diversity. Thinking of genetics as a recipe, may help some people
better understand, genetic counselors say. A slight change in the recipe
may not make much of a difference, but the wrong ingredient or too much
or too little of something, may change the recipe drastically.
Two articles published recently in the New England Journal of Medicine
highlight the risk of cancer associated with specific genes tested in
large populations. The research is important, says Dr. Morrell, because
not every gene mutation carries the same risk. “A
BRCA mutation might lead to an 80 percent risk of breast cancer but an
ATM mutation might have a 20 percent lifetime risk,” she says. “These
are very different, which is why having this information is so valuable.”
The genetic teams at Lynn Cancer Institute and Miami Cancer Institute offer
multidisciplinary care to patients - and often their family members who
may also be affected - to better understand their risks, help them determine
if genetic testing would be beneficial, and assist them with understanding
the results, whether they are positive, negative or inconclusive.
The team also develops personalized cancer prevention plans for “previvors,”
the term used for those with a predisposition to cancer. The plans could
include lifestyle changes, such as specific diet, exercise and stress
reduction recommendations, or lead a discussion about medication options
or even preventive surgery.
Who should consider cancer genetic assessment?
In addition to seeing more men - who don’t often come for genetic
assessment and sometimes don’t understand the implications for their
family members - the doctors would especially like people to consider
assessment if they:
- Have had cancer themselves
- Have an early age of onset for cancer in their family
- Have a family member with multiple types of cancer
- Have a family tree with multiple cancers, especially on one side or the other
- Are a member of certain ancestry groups with higher rates of some genetic
mutations, including those of Eastern European Jewish descent.
Couples who have a family history of cancer and are considering pregnancy
also frequently take advantage of genetic assessment. “If you really
want to be able to tell your children they are not at risk to have a particular
mutation, you need to test both parents,” Dr. Morrell says. “The
offspring can only inherit a mutation that the parents have. Mutations
do not skip a generation and move from grandparent to grandchild without
the parent inheriting it.”
For more information on genetic assessment, testing and counseling at the
Morgan Pressel Center for Cancer Genetics at Lynn Cancer Institute, click
here; for information on Miami Cancer Institute’s Clinical Genetics program, click
here.