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.
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.
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.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 theUnited States.
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.
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.