All About Mammograms
Posted by Nathan Switzer on Tue, Aug 18, 2009
What you need to know about these tests
Every year millions of women in the U.S. willingly bare their breasts to a stranger in the hope of learning they don't have cancer. These women get a mammogram, a crucial tool in the fight against breast cancer. What follows are some basic questions about mammograms with answers from local and national authorities.
Q What is a mammogram, and what is it used for?
A A mammogram is an x-ray picture of the breast. It is the best screening tool for finding breast cancer, reports the
National Women's Health Information Center (NWHIC).
The test is done while you stand or sit in front of a low-dose x-ray machine, and a technologist places your breast-first one, then the other-between two plates that press the breast and flatten it. The
compression, which helps the technologist produce a better picture, may be uncomfortable, but it lasts only a few seconds.
A radiologist interprets the x-rays, looking for suspicious areas or lumps you may not be able to feel or that may not be causing symptoms. If needed, follow-up tests may be ordered by your doctor.
Q What is the difference between screening and diagnostic
mammograms?
A A screening mammogram is a routine test for women who don’t have symptoms of breast cancer. The disease can take many years to develop and may cause no symptoms early on. A mammogram can help find cancer at its earliest stages, when there may be more treatment options and treatment may be more successful. A diagnostic mammogram is a follow-up exam. It may be ordered if a
screening mammogram shows an abnormality or after a woman or her doctor finds something, such as a lump, that warrants further testing.
“It is important that a woman talk to her healthcare provider about any breast changes prior to her annual mammogram. Then, when she comes for her mammogram I can thoroughly evaluate any identified problems” says Denise Farleigh, MD, Medical Director at Providence Imaging Center (PIC).
More images of the breast are taken during a diagnostic mammogram than a screening test.
Q How often should I get a mammogram?
Should I also get an MRI?
A According to the American
Cancer Society (ACS), women 40
and older should have yearly screening
mammograms.
The ACS recommends a yearly MRI
in addition to a screening mammogram
if you have an increased risk of breast
cancer—for example, you have a BRCA1
or BRCA2 gene mutation or have a parent,
sibling or child with either of these
mutations.
“If you have a strong family history of breast cancer
or think you may have increased risk, talk to your healthcare provider about risk assessment.
At PIC, we work closely with genetic counselor Maggie Miller, at the Providence Cancer Center. She reviews family and personal history and determines if you are a candidate for
Breast MRI screening,” explains Dr. Farleigh.
For most women at high risk of breast
cancer, MRI and mammogram screening
should begin at age 30, reports the ACS.
Q What are the benefits and risks of
mammography?
A As good as mammograms are at
detecting breast cancer, they aren’t
perfect, say experts. There are risks of
both false-negative and false-positive
results.
A false-negative result means that a
breast looks normal on a mammogram
but cancer is actually present. False negatives
are rare, according to the NWHIC.
They are more common in younger women
because their breast tissue tends to be
denser than the tissue in older women.
A false-positive result means that
it looks like cancer is present when it’s
not. Women between the ages of 40 and
49 have the highest incidence of false positive
mammograms reports the Radiological Society of North
America.
According to Dr. Farleigh, "When I see something new on a mammogram, I need to investigate further with additional tests until I am satisfied that the new finding is not a cancer."
In addition to screening mammography and breast MRI screening, PIC offers complete breast diagnostic services including: diagnostic mammography, ultrasound, diagnostic MRI, and imaging guided biopsies using stereotactic, ultrasound and MRI guidance. If a woman is diagnosed with breast cancer, we can link her with the Patient Navigators at the Providence Cancer Center to help her access resources during treatment and beyond.
What a radiologist looks for
When a radiologist reads a mammogram, he or she looks for calcifications
and masses (lumps).
Calcifications appear as small, white spots on the x-rays. They are
mineral deposits that may or may not be caused by cancer.
Large calcifications, called macrocalcifications, are often related
to aging, injury or inflammation. They typically don’t require a biopsy
(removal of a small amount of tissue) because they are almost never cancerous.
About half of all women older than 50 have macrocalcifications,
reports the American Cancer Society (ACS).
Tiny specks of calcium, called microcalcifications, can sometimes
signal cancer if they are grouped in a certain way. A radiologist will
carefully evaluate the shape and layout of the calcifications and may
recommend a biopsy.
Masses (lumps) in the breast can be caused by many things. For
example, a mass may be a cyst—a noncancerous, fluid-filled sac—which
is diagnosed with an ultrasound or aspiration, fluid removal with a
needle.
If a mass is partly solid, however, it may be a tumor. The radiologist
will study the size and shape of the mass on the mammogram. He or
she will also see if the mass was present on past mammograms and will
compare how the mass looked on those tests with the current one.
Depending on the radiologist’s findings, a doctor may take a wait-and-see approach—using periodic mammograms to monitor the
mass—or recommend a biopsy.
About 10 percent of women who have screening mammograms
need more testing, such as an additional mammogram, an ultrasound
or a biopsy. But most will learn that they don’t have cancer, reports the
ACS.
To learn more about mammograms and breast cancer, visit www.cancer.org
and www.cancer.gov