What is a
Mammography?
A mammogram is a special x-ray of the breast. It is a
radiological procedure available to detect small cancers
long before they can be felt by you or your doctor.
As the x-rays pass through the breast tissue, an actual
picture of the tissue inside is obtained. This image
allows the radiologist to determine whether or not
cancer is present.
If you are not having any breast problems, you will be
scheduled for a screening mammogram. If you are having
problems, then you should be scheduled for a diagnostic
mammogram.
Common
uses of this procedure.
Mammography is used to diagnose breast diseases in
women. The use of screening mammography can assist in
the detection of disease even if you have no complaints
or symptoms.
While the AMA and ACR recommend that women aged 40 and
older get annual mammograms, the National Cancer
Institute (NCI) says women who are at increased risk due
to a genetic history of breast cancer, or who have had
breast cancer, may need to get mammograms at an earlier
age.
The following are suggested guidelines:
Between the ages of 35 and 40
A woman should have a baseline mammogram
Between the ages of 40 and
50
A woman should have a mammogram once every one or two
years
After the age of 50
A woman should have the mammogram every year
How
does it work?
The breast is exposed to a small dose of radiation to
produce an image of internal breast tissue. The image of
the breast is produced as a result of some of the x-rays
being absorbed (attenuation) while others pass through
the breast to expose the film. The exposed film is
either placed in a developing machine, producing images
much like the negatives from a 35-mm camera, or images
are digitally stored on computer
Benefits vs Risks
|
Benefits |
Risks |
Imaging of the breast improves a physician's
ability to detect small tumors. When tumors are
small, effective treatment and cure are more
likely. |
Radiation exposure. Mammography is an x-ray
imaging procedure. Federal mammography
guidelines limit the radiation used for each
exposure of the breast to 0.3 rad. The exposure
to radiation received from two mammographic
views is equivalent to six months of natural
background exposure. This amount of exposure is
believed to be safe. |
The use of screening mammography increases the
detection of small abnormal tissue growths
confined to the milk ducts in the breast, called
ductal carcinoma in situ (DCIS). These early
tumors cannot harm patients if they are removed
at this stage and mammography is the only proven
method to reliably detect these tumors. |
False Positive Mammograms. Between 5 and 10
percent of mammogram results are abnormal and
require more testing (more mammograms, fine
needle aspiration, ultrasound, or biopsy), and
most of the follow-up tests confirm that no
cancer was present. It is estimated that a woman
who has yearly mammograms between ages 40 and 49
would have about a 30 percent chance of having a
false-positive mammogram at some point in that
decade, and about a 7 to 8 percent chance of
having a breast biopsy within the 10-year
period. The estimate for false-positive
mammograms is about 25 percent for women ages 50
or older. |
Patient Comfort.
During a mammogram, the breast is positioned on the
x-ray machine and is placed between two pieces of
plastic. This gently flattens the breast and exposes as
much of the tissue as possible. Your breasts will be
compressed a few seconds for each x-ray. Although this
will be slightly uncomfortable, it is necessary to
ensure an accurate exam. The discomfort usually subsides
within seconds.
Many women experience increased tenderness of the
breasts prior to menstruation. If this applies to you,
please avoid scheduling your mammogram at this time to
minimize any additional discomfort. |