- (News Target) -- Breast cancer is the leading cause of
death among American women between the ages of 44 and 55. Dr. Gofinan,
in his book, Preventing Breast Cancer, cites this startling statistic along
with an in-depth look at mammographic screening, an early-detection practice
that agencies like the American Cancer Society recommend to women of all
age groups. According to most health experts, catching a tumor in its early
stages increases a woman's chances of survival by at least 17 percent.
- The most common method for early detection is mammography.
A mammogram is an X-ray picture of your breast that can reveal tumor growths
otherwise undetectable in a physical exam. Like all x-rays, mammograms
use doses of ionizing radiation to create this image. Radiologists then
analyze the image for any abnormal growths. Despite continuous improvements
and innovations, mammography has garnered a sizable opposition in the medical
community because of an error rate that is still high and the amount of
harmful radiation used in the procedure.
- Effectiveness of Mammography
- Is mammography an effective tool for detecting tumors?
Some critics say no. In a Swedish study of 60,000 women, 70 percent of
the mammographically detected tumors weren't tumors at all. These "false
positives" aren't just financial and emotional strains, they may also
lead to many unnecessary and invasive biopsies. In fact, 70 to 80 percent
of all positive mammograms do not, upon biopsy, show any presence of cancer.
- At the same time, mammograms also have a high rate of
missed tumors, or "false negatives." Dr. Samuel S. Epstein, in
his book, The Politics Of Cancer, claims that in women ages 40 to 49, one
in four instances of cancer is missed at each mammography. The National
Cancer Institute (NCI) puts the false negative rate even higher at 40 percent
among women ages 40-49. National Institutes of Health spokespeople also
admit that mammograms miss 10 percent of malignant tumors in women over
50. Researchers have found that breast tissue is denser among younger women,
making it difficult to detect tumors. For this reason, false negatives
are twice as likely to occur in premenopausal mammograms.
- Radiation Risks
- Many critics of mammography cite the hazardous health
effects of radiation. In 1976, the controversy over radiation and mammography
reached a saturation point. At that time mammographic technology delivered
five to 10 rads (radiation-absorbed doses) per screening, as compared to
1 rad in current screening methods. In women between the ages of 35 and
50, each rad of exposure increased the risk of breast cancer by one percent,
according to Dr. Frank Rauscher, then-director of the NCI.
- According to Russell L. Blaylock, MD, one estimate is
that annual radiological breast exams increase the risk of breast cancer
by two percent a year. So over 10 years the risk will have increased 20
percent. In the 1960s and 70s, women, even those who received 10 screenings
a year, were never told the risk they faced from exposure. In the midst
of the 1976 radiation debate, Kodak, a major manufacturer of mammography
film, took out full-page ads in scientific journals entitled About breast
cancer and X-rays: A hopeful message from industry on a sober topic.
- Despite better technology and decreased doses of radiation,
scientists still claim mammography is a substantial risk. Dr. John W. Gofman,
an authority on the health effects of ionizing radiation, estimates that
75 percent of breast cancer could be prevented by avoiding or minimizing
exposure to the ionizing radiation. This includes mammography, x-rays and
other medical and dental sources.
- Since mammographic screening was introduced, the incidence
of a form of breast cancer called ductal carcinoma in situ (DCIS) has increased
by 328 percent. Two hundred percent of this increase is allegedly due to
mammography. In addition to harmful radiation, mammography may also help
spread existing cancer cells due to the considerable pressure placed on
the woman's breast during the procedure. According to some health practitioners,
this compression could cause existing cancer cells to metastasize from
the breast tissue.
- 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 in the United States 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 to mammography.
- The risk of radiation is apparently higher among younger
women. The NCI released evidence that, among women under 35, mammography
could cause 75 cases of breast cancer for every 15 it identifies. Another
Canadian study found a 52 percent increase in breast cancer mortality in
young women given annual mammograms. Dr. Samuel Epstein also claims that
pregnant women exposed to radiation could endanger their fetus. He advises
against mammography during pregnancy because "the future risks of
leukemia to your unborn child, not to mention birth defects, are just not
worth it." Similarly, studies reveal that children exposed to radiation
are more likely to develop breast cancer as adults.
- Navigating the Statistics
- While the number of deaths caused by breast cancer has
decreased, the incidence of breast cancer is still rising. Since 1940,
the incidence of breast cancer has risen by one to two percent every year.
Between 1973 and 1991, the incidence of breast cancer in females over 65
rose nearly 40 percent in the United States.
- Some researchers attribute this increase to better detection
technologies; i.e., as the number of women screened for breast cancer rises,
so does the number of reported cases. Other analysts say the correlation
between mammographic screening and increases in breast cancer is much more
ominous, suggesting radiation exposure is responsible for the growing number
of cases. While the matter is still being debated, Professor Sandra Steingraber
offers ways to navigate these statistics. According to Steingraber, the
rise in breast cancer predates the introduction of mammograms as a common
diagnostic tool. In addition, the groups of women in whom breast cancer
incidence is ascending most swiftly blacks and the elderly
are also least likely to get regular mammograms.
- The majority of health experts agree that the risk of
breast cancer for women under 35 is not high enough to warrant the risk
of radiation exposure. Similarly, the risk of breast cancer to women over
55 justifies the risk of mammograms. The statistics about mammography and
women between the ages of 40 and 55 are the most contentious. 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.
- Burton Goldberg, in his book, Alternative Medicine, recommends
that women under 50 avoid screening mammograms, although the American Cancer
Society encourages mammograms every two years for women ages 40 to 49.
Trying to settle this debate, a 1997 consensus panel appointed by the NIH
ruled that there was no evidence that mammograms for this age group save
lives; they may even do more harm than good. The panel advises women to
weigh the risks with their doctors and decide for themselves.
- New Screening Technologies
- While screening is an important step in fighting breast
cancer, many researchers are looking for alternatives to mammography. Burton
Goldberg totes the safety and accuracy of new thermography technologies.
Able to detect cancers at a minute physical stage of development, thermography
does not use x-rays, nor is there any compression of the breast. Also important,
new thermography technologies do not lose effectiveness with dense breast
tissue, decreasing the chances of false-negative results.
- Some doctors are now offering digital mammograms. Digital
mammography is a mammography system in which x-ray film is replaced by
solid-state detectors that convert x-rays into electric signals. Though
radiation is still used, digital mammography requires a much smaller dose.
The electrical signals are used to produce images that can be electronically
manipulated; a physician can zoom in, magnify and optimize different parts
of breast tissue without having to take an additional image.
- First published 8-15-5