Network News - Winter/Spring 2010 - Canadian Breast Cancer ...

Familial Breast Cancer and No BRCA1/2 Mutation?
Uninformative Results and How the Familial Breast Cancer Research Unit
is Seeking Answers
By Jillian Alston, MD Candidate
In the mid-nineties, the discovery
of the BRCA1 and 2 mutations
answered some of the questions
that many had about the alarming
number of breast and/or ovarian
cancers in their family. Furthermore, a
woman from such a family who has not
been diagnosed with cancer can now
establish her risk of breast cancer by
being tested for her family’s hereditary
gene. Women who receive positive
results struggle with how to manage
their increased risk. Fortunately there
are recommendations for BRCA1/
BRCA2 carriers with ever-growing
research to improve the management
and prevention of cancer in these
families. I am aware that I have
immensely minimized the complex
nature of the genetic testing process
and all of its considerations, including
its influence on psychological wellbeing
and family dynamics. As well, in
no way do I wish to oversimplify the
difficulty of one’s journey of living with
a BRCA1/2 mutation.
Jillian Alston
However, the focus of this article
is on those women who have an
overwhelming number of relatives
diagnosed with breast cancer – but
who do not have a known mutation in
their family. Approximately 15-20% of
women who are diagnosed with breast
cancer have a strong family history of
breast cancer. This number includes the
5% incidence of breast cancer that is
found in women with a mutation in one
of the two known breast cancer genes,
BRCA1 and BRCA2. This indicates that
the majority of women who have had
genetic testing for their familial breast
cancer have no specific genetic reason
for the family history, in that they
receive an “uninformative result.”
Women who have a significant 1 breast
cancer history in their family are two to
four times more likely to develop breast
cancer than females without a significant
family history, even if they do not
have a BRCA1 and BRCA2 mutation. 2
There is currently little information
available to inform these women and
their physicians about screening and
prevention practices. Unlike BRCA1/2
mutation carriers, there is no established
standard for offering earlier screening
(either mammography or MRI), or
for offering chemoprevention or
prophylactic surgeries (e.g. bilateral
mastectomy or bilateral salpingooophorectomy).
Dr. Steven Narod and his research team
at the Familial Breast Cancer Research
Unit of Women’s College Research
Institute in Toronto, are trying to
improve the care of these families by
initiating the research study Risk Factor
Analysis of Familial Breast Cancer. This
is an unprecedented long-term study
of women with strong family histories
of breast cancer who do not carry a
mutation in one of the two breast cancer
genes (BRCA1/BRCA2).
The study involves testing for other
positive genetic markers of breast cancer
as well as examining the interaction
between other various factors that
may be associated with breast cancer
development in women from highrisk
families. Some of these include
Vitamin D levels, insulin levels, dietary
factors, demographic characteristics and
others factors. As well, the study will
examine the effectiveness of prevention
strategies that various women use. The
goal is to hopefully develop future
recommendations for the prevention and
management of familial breast cancer.
If you are concerned about the incidence
of breast cancer in your family or if you
are concerned about breast cancer with
the future generation of your family, the
research team invites you to take part
in this study. The team is looking for
women who have a significant family
history of breast cancer and who have
no known BRCA1/2 mutations in their
family.
For more information about the
study, or to see if you are eligible to
participate, please visit:
http://www.womensresearch.
ca/noncarrierstudy/index.php.
Alternatively, you may contact Jill by
email at jillian.alston@wchospital.ca or
call 416-351-3800 ext 2715.
The Familial Breast Cancer
Research Unit
World-renowned research to improve the
lives of families with familial breast cancer
Dr. Steven Narod
The Familial Breast Cancer Research
Unit is a division of the Women’s
College Research Unit. Under the
direction of Dr. Steven Narod, the
world’s most cited breast cancer
researcher, the unit conducts worldclass
research that contributes to the
prevention and management strategies
for women with familial breast cancer
and their families.
The unit offers a service of genetic
counsellors that support women and
their families through the genetic testing
Network News Winter/Spring 2010 31