Health Risks & Environmental Issues
X-Rays and Mammograms Increase Cancer Risk
by Rose Marie Williams, MA
X-Rays and Mammograms
Increase Cancer Risk
"Each and every incremental exposure to any form of nuclear radiation increases the risk of cancer. It is persistent, deadly, silent, and unseen," declares Janette D. Sherman, MD, in her book, Life's Delicate Balance. X-rays are the most commonly known form of man-made radiation energy.1
It is well understood that X-rays serve as useful diagnostic tools. Radiation therapy has become an integral part of conventional medical treatment. Radiation techniques and X-rays have become so common and pervasive in conventional medicine that their negative impact on health has gone completely ignored. This issue of the Townsend Letter is focused on cancer prevention and treatment. In a continuing effort to help readers become wiser consumers, this column will focus on raising awareness about radiation as a contributing cause of cancer.
High radiation exposure kills, while repeated low-level exposure damages cells, resulting in impairment to cell division, hormonal function, and repair mechanisms. Radiation exposure to tissue results in disruption of chemical bonds, leading to cell mutation, DNA damage, or tissue death.1
Radiation's risk in the development of lung cancer, leukemia, and thyroid cancer is well-established. Women treated with radiation for tuberculosis, scoliosis, and acne have an increased risk of breast cancer. Women treated with radiation for postpartum breast swelling and benign breast disease have an increased risk of breast cancer. "Even 'routine' chest or dental X-rays carry some risk of cancer."1
Many dentists recommend yearly X-rays for their patients. Yearly X-rays, however, are not an absolute necessity. It is worthwhile discussing these matters with one's dentist. Medical consumers have a right to participate in their health care, and open dialogue should be welcomed. As the primary advocates for their children, parents should be extra-cautious about unnecessary X-rays, because young bodies are even more vulnerable to radiation damage.
Exposure to low levels of radiation from any source generates cumulative health risks, and unrepaired damage to genes from X-rays also accumulates.1 Despite this, most medical professionals are taught, and therefore advise their patients, that the amount of radiation is minimal, less than an airplane flight to France.
X-Rays and Secondary
A new study suggests exposure to chest X-rays may increase the risk of breast cancer for women with BRCA1/2 mutations and that exposure for women before the age of 20 "may be linked to particularly heightened risk." The study found women with the BRCA1/2 mutations exposed to chest X-rays were 54% more likely to develop breast cancer than women not exposed. Women who had been exposed to X-rays before the age of 20 had a 2.5-fold increased risk of developing breast cancer before reaching age 40, compared to women not exposed.2
Dr. David E. Goldberg, PhD, Chief of the Genetic Epidemiology Group at the International Agency for Research on Cancer in Lyon, France, and lead author of the study suggests that "young women who are members of families known to have BRCA1 or BRCA2 mutations may wish to consider alternatives to X-ray, such as MRI."2
According to the National Cancer Institute (NCI), "cancer survivors have a 14% higher risk of developing a new primary malignancy compared to the general population." Risk factors for the second cancer may be the same as those associated with the first cancer (smoking, alcohol use, diet/nutrition, genetic factors). The NCI failed to mention environmental risk factors, but did acknowledge that secondary cancers for some people may result from the radiotherapy or chemotherapy used to treat the first cancer.3
Radiation has been used since the 1920s to treat certain cancers of the oral cavity, esophagus, respiratory tract, lymphoma, female genital tract, testis, and brain. Radiation is used to shrink tumors, but it increases the risk of developing second cancers years later. The risk is dependent upon the type and dose of radiation received; the amount of body treated (treatment field); part of the body irradiated and tissue sensitivity; and age at time of treatment. Some organs are considered "radiation sensitive," while others like the prostate are generally "radiation-resistant," though Dr. Sherman reminded me that surrounding tissue is very susceptible to radiation damage.3
The "breast, thyroid and lung are particularly sensitive to the carcinogenic effects of radiation," as has been demonstrated by Japanese atomic bomb survivors and by patients receiving radiation therapy. Children, adolescents, and young adults are particularly at risk of radiation effects later in life. Breast cancer was the most frequently diagnosed solid tumor among women treated for lymphoma prior to age 30.3
To mammogram – or not to mammogram? That is a most difficult question. Even though mammograms have been promoted as the gold standard in detecting breast cancers, Dr. Susan Lark points to their high rate of false-positives, which leads to more invasive procedures, more testing, more X-ray exposure, and unnecessary stress burden. The false-negatives fail to identify problem areas in possible need of treatment, allowing a missed cancer to escalate to a more serous stage of disease.4
Dr. Rosalie Bertell indicates that mass screening programs may actually cause more cancers by radiating large population groups. Dr. Bertell cites a Canadian study involving 50,000 women between the ages of 40 and 49. In the group who had mammograms, 44 women developed breast cancer, while only 29 women developed the disease in the group that did not have mammograms. She does suggest that a mammogram can be a useful diagnostic tool if a woman discovers a mass.1
The increased cancer risk from mammography was well-established before the NCI and the American Cancer Society (ACS) launched their large scale routine screening of pre-menopausal women in the 1970s. In 1972, the National Academy of Sciences, the world's leading authority on radiation, warned of a "relative risk of about .08% increase in the spontaneous rate of breast cancer per rad of exposure."5
In his book, The Politics of Cancer Revisited, Dr. Samuel Epstein, outspoken critic of the cancer industry, estimates that a 20% increased risk of breast cancer could be expected for pre-menopausal women exposed to ten yearly mammograms with two rads per exposure. Women are not warned of any potential risks, while "being falsely assured of the benefits." Exposure levels have since been reduced, but women are still not properly informed of the risks, while questionable benefits are still highly promoted.5
Despite the radiation exposure, women cannot even depend on the accuracy of mammograms. According to a 1996 report in the journal Archives of Internal Medicine, radiologists missed positive cancers in 21% of patients – judged ten percent of cases to be cancer that were not – and misread 42% of benign lesions as cancerous.6
Every October, we are subjected to the heavy media explosion that mammography saves lives. But does it? A closer look at the studies does not support this claim. Two Swedish scientists reviewing all mammography trials found sufficient flaws and inconsistencies to nullify the studies' claims of a benefit from mammography. Their meta-analysis concluded, "there is no reliable evidence that mammography screening decreases breast cancer mortality." Since "mammography screening for breast cancer is unjustified," Dr. John R. Lee believes that "physicians should not order routine mammography screening."7
The newest thing being promoted to women is computer-aided detection mammography (CAD). Mammogram films are converted into digital files that can be analyzed by computer software to check images and mark suspicious areas. Radiologists can view these images in conjunction with their own readings.8 The new technology was found to be "less accurate than interpretation without the computer's help." The "computer software designed to improve mammogram interpretation may actually make it worse," according to a study reported in the April 5, 2007 issue of the New England Journal of Medicine.8
The new software resulted in 32% more women being recalled for additional tests and 20% more women undergoing breast biopsy, though most results showed no breast cancer. The software may actually increase detection of the least dangerous breast cancers (in situ), which grow so slowly they often would rarely come to clinical attention without screening. The software did not prove to be any better in detecting more dangerous invasive breast cancers.8 This new and questionable technology is also covered by insurance.
Follow the Money
One must ask why there is such a strong emphasis for women to get annual mammograms. The original push was for women to begin annual mammograms around age 50. A new push recommends women get their first mammogram beginning at age 35, or as young as their twenties, if they have a family history of breast cancer. This advice may do more harm than good. Mammograms are even less reliable for younger women with denser breast tissue.
Women who have had breast cancer once, or who have a blood relative (female or male) who has had the disease, are already at greater risk for developing breast cancer. Urging this highly susceptible population to have mammograms, a procedure known to damage cells and increase cancer risk, is totally immoral in my estimation, especially when alternative diagnostic tools are available.
Women are not given all the facts, merely all the fears. No one wants cancer, and many women unquestionably follow the propaganda that mammograms save lives. Not only does the incidence of breast cancer continue to escalate; it is striking younger women all the time. Mammograms can detect cancer, but also misread cancer.
Meanwhile, accumulated radiation from mammograms with yearly hits to the same tissue contributes to gene damage and cancer development. This brings to mind the question of the chicken and the egg and the question: which came first? Will we ever know what role mammography plays in contributing to the increased number of breast cancers? Is it possible that fewer mammograms and less radiation would result in a drop in breast cancer?
When a positive diagnosis is made, doctors assure patients it was lucky they had a mammogram to find the cancer, so that treatment can start right away. How many patients are ever advised that repeated mammograms may have promoted the cancer in the first place? John Gofman, physicist and MD, estimates that women between the ages of 50 and 64 who are exposed to one mammogram have one chance in 2000 of a mammogram-induced breast cancer. After 15 exams (15 chances in 2000), the risk of a mammogram-induced breast cancer increases to one chance in 133.1
By my calculations, if a woman has 25 mammograms (one p/yr from age 50 to 75), her risk of developing breast cancer increases to one in 80 or greater because of the synergistic effect of bioaccumulation and DNA damage. This does not include radiation from a lifetime of other medical or dental X-rays, CT scans, or therapeutic applications, nor does it include exposure from radioactive fallout that continuously rains down on us from nuclear power plant emissions. These risk factors are not receiving the attention they deserve.
The NCI and the ACS campaigned for free screenings in the 1970s. John C. Bailar III, editor of the NCI journal questioned mass screenings in 1976 when he wrote, "The possible benefits of mammography have received more emphasis in the clinical literature than its defects." He suggested, "mammography may eventually cause more deaths from breast cancer than it prevents."1
A 1998 edition of the Merck Manual indicates that a woman who has annual mammograms for ten years has a 50% chance of having at least one biopsy, even if she never develops breast cancer. Joseph Mercola, MD, estimates that at $100 per mammogram times 62 million American women over age 40 added to $1000 per biopsy for one to two million women generates a hefty eight billion dollars annually.6 What industry would want to deny their stockholders a share of this lucrative market?
The late Dr. John R. Lee, a great champion of natural solutions for women's health problems, also recognized the huge profitability of detecting and treating breast cancer, and described it as a growing industry generating billions of dollars. It starts with mammograms, followed by biopsies, surgeries, chemotherapy, radiation, and drugs, all of which create a substantial income stream for hospitals, physicians, their support staff, corporations who make all the equipment, and, especially, the pharmaceutical industry.7
There is little financial incentive to halt the conveyor belt of profitable cancer treatment to look at real cancer causes and prevention. Al Gore might even say it would yield an inconvenient truth. The vested interests will not easily give up a lucrative business. If women want something different, they will have to demand it. If conventional medicine was sincere about preventing breast cancer, safer diagnostic procedures would be promoted in place of mammograms and be covered by insurance, and greater attention would be focused on environmental pollutants in our air, water, soil, and food.
Rose Marie Williams, MA
156 Sparkling Ridge Road, New Paltz, NY 12561
1. Sherman J. Life's Delicate Balance: Causes and Prevention of Breast Cancer. New York: Taylor & Francis; 2000.
2. Chest X-ray exposure may increase likelihood of breast cancer. Science Daily. June, 2006. Am. Soc. of Clinical Oncology. Available at: http://www.sciencedaily.com/releases/2006/06/060627105051.htm. Accessed May 16, 2007.
3. Maisey H. Can radiation therapy influence the development of second cancers? National Cancer Institute. Available at: http://www.cancer.gov/templates/doc. Accessed May 16, 2007.
(Bad link: Try http://www.cancer.gov/newscenter/benchmarks-vol7-issue1/page1)
4. Lark S. Women's health update. August 8, 2004. Available at: firstname.lastname@example.org. (Bad link.)
5. Epstein S. The Politics of Cancer, Revisited. CA: Parissound Pub; 1999.
6. Mercola J. Medicine mum on mammography: do the math. Available at: http://www.mercola.com/display. Accessed May 17, 2007.
(Try: http://www.mercola.com/2000/oct/29/thermography.htm You must provide your e-mail to access articles.)
7. Lee JR, MD. What Your Doctor May Not Tell You About BREAST CANCER. New York: Warner Books; 2002.
8. Computer-Aided Interpretation of Mammograms: Questions and Answers. NCI. Available at: http://www.cancer.gov/newscenter/pressreleases/CADmammographyQandA. Accessed May 17, 2007.