What Is Breast Cancer?
Tumors are swellings or growths. They are classified as
either benign or malignant. Although benign tumors are
not harmful in themselves they can cause harmful obstruction
or pressure and in such cases require removal. In contrast,
malignant tumors, known as cancers, are harmful. The cells
that make up a malignant tumor are not sensitive to mechanisms
that normally control cell division. The natural cell life
includes cells that divide to create new tissue as older
cells die off. In the case of cancer, the cancer cells
do not die off at the right rate. The result is the growth
of an extra mass of tissue, or a tumor. Cancer cells can
also migrate through the body and invade other parts. This
process is called metastasis.
Breast cancer is a malignant tumor that develops from cells
of the human breast. Without medical treatment, this malignant
tumor may invade surrounding tissues or spread (metastasize)
to distant areas of the body, preventing normal function
of vital organs and damaging essential systems, eventually
leading to death. Over the course of a lifetime, one in
eight women will be diagnosed with breast cancer.
Risk Factors
• Age: As with most cancers, age is a major risk factor.
In fact, growing older is the biggest risk for breast
cancer. 77% of new cases and 84% of breast cancer deaths
occur in women aged 50 and older. More than 80% of
breast cancer cases occur in women over 50.
• Genetic Factors and Family History of Breast Cancer:
Some families appear to have a genetic tendency for breast
cancer. The exact mechanism is still not clear, but research
suggests that breast cancer is caused by the gradual
accumulation of genetically damaged cells over time.
Two variant genes
have been found that appear to account for this, which
researchers have named BRCA1 and BRCA2. The genes p53
and BARD1 also appear to be a factor, as well as BRCA3
and
Noey2 (the latter is a disease inherited only from the
father's side of the family).
• Gender: Breast cancer is the most common cancer
to affect women. The risk of breast cancer is clearly
related to
hormonal influences, but the exact mechanism of how
these affect the disease is still not totally clear.
High levels
of estrogen during a woman's reproductive years,
especially
when they are not interrupted by the hormonal changes
of pregnancy, appear to increase the chances that
genetically damaged cells will grow and cause cancer.
Women carrying
mutated BRCA1 and/or BRCA2 genes appear to have a "head start" in this process. Men can also get breast cancer, but it is much less common,
accounting for less than 1% of all breast cancers.
• Early Menstruation and Late Menopause: Women who started
menstrual periods early (before age 12) or went through
menopause late (after age 55) are at higher risk. Each
is directly related to the body having produced estrogen
for a longer period of time. Also, women who have never
had children or who had them only after the age of 30
have an increased risk. Again, this is related to the
body producing
estrogen uninterrupted for a longer period of time.
• Oral Contraceptives (birth control pills): In the past,
oral contraceptives contained high levels of the hormones
estrogen and progesterone, and use of these contraceptives
showed a small link to an increased risk for breast cancer.
Today’s birth control pills contain very low doses of
estrogen and progesterone.
• Hormone Replacement Therapy: Use of HRT for more than
five years has been shown to slightly increase the risk
of breast cancer; this risk increases with longer use.
• Overweight: Being overweight has shown to increase
the risk, due to the increased production of estrogen.
• Alcohol Consumption: Excessive alcohol use (more than
1-2 drinks a day) has been associated with an increased
risk of breast cancer. This seems to be caused by the
liver’s decreased ability to regulate blood estrogen
levels.
• Chemicals: Some studies have pointed to exposure to
estrogen-like chemicals that are found in pesticides
and other industrial
products as a possible increased risk of breast cancer.
• DES: Women who took diethylstilbestrol (DES) to prevent
miscarriage may have an increased risk of breast cancer.
• Radiation: People exposed to radiation, particularly
during childhood, may face an increased risk for breast
cancer in adulthood. Especially at risk are those that
received chest irradiation for prior cancers.
• Additional Risk Factors: Some studies show previous
breast, uterine, ovarian, colon cancer, and a strong
history of
cancer in the family may increase the risk for breast
cancer.
Diagnosis
Treatments
Resources
breastcancer.org
111 Forest Avenue 1R
Narberth PA 19072
www.breastcancer.org
“breastcancer.org is a nonprofit organization dedicated
to providing the most reliable, complete, and up-to-date
information about breast cancer. Our mission is to help
women and their loved ones make sense of the complex medical
and personal information about
breast cancer, so they can make the best decisions for
their lives.”
The Susan G. Komen Breast Cancer Foundation
5005 LBJ Freeway, Suite 250
Dallas, TX 75244
Telephone: 972-855-1600
Helpline: 1.800 I'M AWARE®
www.komen.org
“For more than 20 years, the Susan G. Komen Breast Cancer
Foundation has been a global leader in the fight against
breast cancer through its support of innovative research
and community-based outreach programs. Working through
a network of U.S. and international Affiliates and events
like the Komen Race for the Cure®, the Komen Foundation
is fighting to eradicate breast cancer as a life-threatening
disease by funding research grants and supporting education,
screening and treatment projects in communities around
the world.”
National Breast Cancer Foundation, Inc.
2600 Network Blvd.
Suite 300
Frisco, Texas 75034
www.nationalbreastcancer.org
“The National Breast Cancer Foundation mission is to
save lives by increasing awareness of breast cancer through
education and by providing mammograms for those in need.”
