Breast cancer is the most common cancer among American women (American Cancer Society), but only 5-10 percent of breast cancer cases are hereditary. Of those cases, roughly 20-25 percent are linked to mutations in the BRCA1 and BRCA2 genes (BRCA stands for BReast CAncer susceptibility). View the infographic above for more on the genetics of breast cancer. For more information on breast cancer, visit the website for Dana-Farber’s Susan F. Smith Center for Women’s Cancers Breast Oncology Program: http://www.dana-farber.org/Adult-Care/Treatment-and-Support/Breast-Cancer.aspx

1. Breast Cancer and Genetics
of breast cancer cases
are hereditary
“An alteration or a
mutation in a gene
(BRCA 1, 2)
does not equal cancer,
and of these, BRCA
mutations are responsible
for approximately 20–
25% of the diagnoses.
it just means there is
an increased risk.”
Huma Rana, MD,
Cancer Geneticist,
Dana-Farber Cancer Institute
New Breast Cancer Cases Every Year
new cases
of invasive breast cancer
232,340
in women in
2013
cases of carcinoma
in situ (CIS) in 2013
(non-invasive and earliest form of breast cancer)
64,640
Risk of Cancer if you have
BRCA 1, 2 mutations
Women with inherited alterations in BRCA 1, 2 have a
40-80%
chance of developing breast
cancer during their lifetimes.
5-10%
Family Members
with Breast Cancer
risk
factors
5–10% of women have a mother
or sister with breast cancer, and
about twice as many have either
a first-degree relative or seconddegree relative with breast cancer.
for
breast cancer
• Age
• Reproductive and
menstrual history
• Oral contraceptives
• Hormone replacement
therapy
• Radiation exposure
• Alcohol intake
• Obesity
Bilateral preventative
mastectemy can reduce risk
of breast cancer by 90%.
Curable Breast Cancer
Percent of Survival
93%
88%
81%
74%
Stage 0
Stage I
Stage IIA
Stage IIB
67%
41%
49%
15%
Stage IIIA
Stage IIIB
Stage IIIC
Stage IV
Sources
•
•
•
•
•
Dana-Farber Turning Point, 2009: http://www.dana-farber.org/uploadeFiles/
Library/newsroom/publications/turning-point/2009/TurningPoint_2009.pdf
NCI – Genetics of Breast and Ovarian Cancer: http://www.cancer.gov/
cancertopics/pdq/genetics/breast-and-ovarian/HealthProfessional/page1
American Cancer Society: http://www.cancer.org/cancer/breastcancer/
overviewguide/breast-cancer-overview-key-statistics
American Cancer Society: http://www.cancer.org/cancer/breastcancer/
overviewguide/breast-cancer-overview-survival-rates
“Outsmart Your Genes: Understanding BRCA 1/2 Cancer Risk” by Huma Q. Rana, MD, Dana-Farber Cancer
Institute, July 2013
S USAN F. S MITH C ENTER
FOR
W OMEN ’ S C ANCERS