Mammograph is a diagnostic tool used to screen breast
cancer in hopes that breast cancer can be detected at its earliest stage and
patients can be treated early enough to increase their odds of survival.
For a long time, mammography is recommended for women aged
40 to 49 who are believed at high risk of breast cancer. However, the potential
benefits and particularly the risks of the modern technology are seldom
discussed with patients.
In today's issued of the Annals of Internal Medicine, the
American College of Physicians (ACP) issued new clinical guidelines for
screening mammography for women age 40 to 49, emphasizing that patients should
be told of both benefits and risks of mammograms as the risk of the procedure
has become evident.
But the guidelines are ambiguous, critics said, which only
recommend that clinicians should help patients decide whether or not to take
mammograms. The guidelines do not reveal much of real benefits and risks
associated with use of mammograms in detail.
Mammograms are touted by many doctors as the best screening
tool for detecting breast cancer while some urge caution.
Is mammography effective enough in diagnosing
The problems with this
screening method include false positives and false negatives and the risk of
According to a Swedish study of 60,000 women, cited by
newstarget.com, 70 percent of the mammographically detected tumors weren’t
tumors at all.
70 to 80 percent of all
positive mammograms do not show any presence of breast cancer. These false
positives may be responsible for the increased survival rate if any associated
with mammogram screening, critics suggested.
The false positives are likely to result in unnecessary
medical intervention and emotional stress.
For instance, a positive resulting from mammograms is likely to lead to
invasive biopsy, which could do more harm than good. In some cases, the false
diagnosis could lead to loss of a healthy breast or even life.
On the other hand, mammograms have a high rate of missed
diagnosis of breast cancer, resulting in false negatives, which can delay
treatment and eventually lead to loss of a woman' life.
Dr. Samuel S. Epstein, professor of
Environmental Health Department in
Chicago, was cited as claiming in his book
"The Politics of Cancer" that 25 percent of breast cancer cases are
missed in women aged 40 to 49 when mammography is used for screening.
According to a report by newstarget.com, the rate of false
negatives estimated by the National Cancer Institute (NCI) is even higher, 40
percent among women ages 40-49. Mammograms result in high rates of false
negatives in younger women, whose breasts are denser, making it harder to
detect breast cancer.
women, the false negatives are twice as likely to occur.
In addition to the uncertainties of screening results, one
thing is certain:
breast issue, which is very sensitive to ionizing radiations such as x-ray used
Ionizing radiations are
the best studied cancer causing agent in the world and the human history and
were recognized by the
government as a carcinogen in 2005 although the risk has been known for decades
to say the least.
The dose used in the current mammography is relatively smaller
than that used in the early days such as in 1970s, about 1 rad versus 5 to 10
But one exposure to the reduced
dose would still increase the risk for breast cancer by one percent in women
aged 35 to 50, according to Dr. Frank Rauscher, former director of the National
Cancer Institute, cited by newstarget.com.
Some such as Russell L. Blaylock, MD, estimated that annual radiological
breast exams increase the risk of breast cancer by two percent.
In the 1960s and 70s, women received 10 screenings a year
without being informed of the potential cancer risk resulting from
Dr. John Gofman, a prominent
nuclear scientist and physician who retired now from the University of
California at Los Angeles estimated that 75 percent of breast cancer cases are
related to exposure to x-ray exposure including that used in mammography and
chest x-ray although he acknowledged that other factors such as diet and
environment also have an effect of the overall risk.
The medical industry downplays repeatedly the risk of medical
x-ray saying that compared to other cancer risks, the risk from x-ray is small,
or the benefits outweigh risks.
studies show that exposure to x-ray may be responsible only for a few percent
of the total cancer risk, but sponsorship for such studies are not always clear
and whether or not there is conflict of interest remains unknown.
The risk of mammograms may be greater for about 30 percent
of women who carry faulty genes such as BRCA 1 and 2, according to an early
The study of 1,600 women with
BRCA 1 and 2 mutations published in the June 27 2006 issue of Journal of Clinical
Oncology shows that these women were 54 percent more likely to develop breast
cancer if they had ever had a chest x-ray.
Exposure to radiation before age 20 doubled the risk of breast cancer
before their 40th birthday.
Dawn Prate reported at newstarget.com that "Women
Cancer research has also found a gene, called oncogene AC, that is extremely
sensitive to even small doses of radiation. A significant percentage of women
have this gene, which could increase their risk of mammography-induced cancer.
They estimate that 10,000 A-T carriers will die of breast cancer this year due
The incidence of ductal carcinoma in situ (DCIS), a form of
breast cancer has increased by 328 percent since introduction of mammogram
screening and 200 percent of the increase is allegedly caused by mammography,
which raises breast cancer risk by the radiation used and pressure placed on
the women's breast during the screening procedure, according to Dawn
It's believed that pressure on
breasts may cause existing breast cancer cells to spread to other locations.
The risk of radiation is more significant in younger women. Evidence
released by the National Cancer Institute cited by newstarget.com shows that mammography
would cause 75 cases of breast cancer for every 15 identified. The mortality of
breast cancer in young women who received annual mammograms increased by 52
percent, according to a Canadian study, cited by Prate.
"A 1992 Canadian National Breast Cancer Study showed
that mammography had no positive effect on mortality for women between the ages
of 40 and 50. In fact, the study seemed to suggest that women in that age group
are more likely to die of breast cancer when screened regularly." Dawn
Prate reported at newstarget.com.
While there is still an ongoing debate on the medical value
of mammography, evidence suggests that the screening method does not help save
lives of women aged 40 to 49.
instance, a 1997 consensus panel appointed by the National Institute of Health
concluded that no evidence suggests mammograms for this age group save lives
and they may even do more harm than good. The panel advises that women weigh
the risks when considering a mammogram.
Those who rely on screening to reduce their risk of death from
breast cancer may consider alternative screening methods such as thermography
and M.R.I. scan as these screening procedures are generally recognized as effective
and safer tools when it comes to detection of breast cancer.
The bottom line is, a health observer with foodconsumer.org
suggests, that no matter how accurate or harmless a diagnostic tool such as
mammography is, these procedures are not meant to prevent breast cancer from occurring
or being developed.
These tools are used
to find breast cancer in its earliest stage and treat the patients early, which
some doctors believe help increase the odds of survival.
Those who really want to prevent breast cancer should know
the real risk factors for breast cancer and eliminate the risks in their life
to reduce their odds of developing breast cancer, the health observer said.
He said when one was diagnosed with breast
cancer, she is already in a defensive position.
Those who want to be free of breast cancer should think more
about prevention than mammogram screening, he suggested.
Click here for full text of the Guidelines.
Click here for
NIH breast cancer risk calculator.