Even if there is some discomfort, it doesn't last long, and the rewards far outweigh this drawback. Most people know someone who has been diagnosed with breast cancer. It's understandable that women may fear getting a mammogram because there is a chance of getting bad news. This anxiety is completely normal, but there is a good reason to put these worries aside and follow through with the procedure.
First, not all abnormalities found during an exam indicate breast cancer. In most cases, lumps are not cancerous. Also, early detection is vital to survival. Detecting cancer during the initial stages offers women a five-year survival rate of 98 percent. The American Cancer Society recommends annual screenings beginning at age However, women with a family history of breast cancer or other risk factors may need to be screened earlier.
Women with family members diagnosed before age 40 are especially at risk. If you're considered to be high risk, you can have genetic testing to determine your actual risks for breast cancer. Breast cancer is prevalent. Early detection can mean the difference between life and death, so it makes sense to take this advantage so you can live a long and healthy life.
All these excuses amount to nothing if you're diagnosed with breast cancer in its late stages. Your chances of recovery are much lower if this disease is diagnosed in later stages. Using 3D mammography also lowers call back rates by 17 to 40 percent. However, mounting scientific evidence indicates that mammography may not only be far less effective than we have been led to believe, but that it also has numerous drawbacks that are affecting women on a massive scale. Read on to learn about the major drawbacks of mammography, what the research recommends for breast cancer screening, and about promising breast cancer detection alternatives.
Mammography screening for breast cancer was first introduced in the late s, and by the early s, it had been widely incorporated into clinical practice.
Prior to the widespread use of mammography, breast cancer detection tests were primarily based on breast self-exams and clinical breast exams performed by physicians. In the very early days of mammography, this test was used only in women at high risk for breast cancer; this included women who had a previous history of breast cancer, had a mother or sisters with breast cancer, or were over 50 years of age.
Fast-forward to the present day, and it is quite apparent that the use of mammography has increased dramatically. According to recent data, Despite this massive increase in the use of mammography, there is a substantial body of research indicating that the widespread, overenthusiastic practice of mammography over the past few decades has had little to no effect on breast cancer mortality rates 2.
In fact, the research indicates that mammography screening may do more harm than good. Mammography has demonstrated a number of adverse effects, including breast cancer overdiagnosis, unnecessary breast cancer treatment, undue psychological stress, excessive radiation exposure, and a serious risk of tumor rupture and spread of cancerous cells 3 , 4.
If mammography was effective at reducing rates of advanced breast cancers, a reduction in the incidence of advanced tumors in the women who received the screening should have been observed.
However, no difference was found in the incidence of advanced tumors between the screened and unscreened groups. In addition, significant overdiagnosis of breast cancer was found in the screened group—approximately one out of every three invasive tumors and cases of ductal carcinoma in situ DCIS was found to represent breast cancer overdiagnosis.
This meant that, due to screening mammography, healthy women were diagnosed with breast cancers. These women subsequently had to deal with the severe psychological distress of a cancer diagnosis, as well as the numerous physical harms of cancer treatment, when in fact their tumors were not cancers that necessitated treatment at all 5.
A systematic review published several years prior found very similar results; in the United Kingdom, Canada, Australia, Sweden, and Norway, the overdiagnosis rate in organized breast screening programs was 52 percent, meaning one in three cancers in the screened population was overdiagnosed 6. Further research has found that mammography screening has led to an increased detection of small tumors, but only a modest decrease in the incidence of advanced tumors.
Many of the small tumors being detected by mammography represent breast cancer overdiagnoses. These small tumors are growths that, if left alone, would never progress to an advanced stage. However, mammography is diagnosing them as cancer, which is in turn causing countless women to be convinced to undergo cancer treatment, with all its harm and side effects, and without any benefit. In regards to the modest reduction in large breast tumors noted above, this reduction has been attributed to improved breast cancer treatment, not to screening mammography 7.
Mammography has a tendency to selectively identify tumors with favorable molecular features, which are features that make breast cancer treatment easier, offering a better prognosis.
This is due to the fact that tumors with favorable characteristics tend to grow more slowly, so there is a larger window of time in which they can be detected by screening mammography. When screening mammography is used, these favorable tumors tend to be diagnosed long before they would begin to cause symptoms.
This phenomenon is called length-bias sampling and refers to a statistical distortion of results that occurs when screening identifies disease cases before the onset of symptoms, making it appear as though survival time is increased for the particular disease due to screening.
However, favorable tumors typically respond to treatment equally effectively at clinical presentation when symptoms appear as they do when diagnosed via mammography, so earlier detection through screening mammography does not translate into a reduction in breast cancer mortality 8.
Breast tissue density affects the ability of mammography to successfully detect tumors. Low-density breast tissue makes it easier for mammography to visualize tumors than does higher-density breast tissue.
In the fatty breast, mammography sensitivity is 98 percent; in the very dense breast, the sensitivity goes down to as low as 48 percent 9. This is a significant issue because in postmenopausal women the subgroup of our population that undergoes regular mammography screening , high-density breast tissue is associated with an increased risk of breast cancer as well as with the presence of tumors with more aggressive characteristics, such as larger tumors and estrogen receptor-negative tumors.
The relative ease with which mammography detects favorable tumors has led to an overestimation of the effect of screening mammography on breast cancer mortality The current recommendations for mammography screening have led women to start screening at a younger age and also to receive more frequent screening; this has amplified the amount of radiation to which the breasts are being exposed, and the effects are not trivial.
In addition, women who are exposed to radiation for other purposes or women who are carriers of the BRCA breast cancer susceptibility gene are at an even higher risk of experiencing adverse effects from mammography radiation While not a direct reflection of the impact of mammography on breast cancer risk, other studies examining the effect of diagnostic chest x-rays on breast cancer risk have found that medical radiation exposure increases breast cancer risk Mammography involves compressing the breasts between two plates in order to spread out the breast tissue for imaging.
Not surprisingly, this can cause significant pain. However, there is also a serious health risk associated with the compression applied to the breasts. Only 22 pounds of pressure is needed to rupture the encapsulation of a cancerous tumor The amount of pressure involved in a mammography procedure therefore has the potential to rupture existing tumors and spread malignant cells into the bloodstream There is significant bias in the medical literature regarding mammography.
A literature review of articles in the journal Evidence-Based Medicine found that a significant number of studies examining the effectiveness of mammography were published by interest groups and authors with vested interests in mammography screening. Scientific journal articles on breast cancer screening written by authors who have a vested interest in the practice of mammography tend to emphasize the potential benefits of mammography, while downplaying or outright rejecting the major harms such as overdiagnosis and overtreatment.
Authors may have a vested interest in promoting mammography if they are receiving income from mammography screening programs or if they are contributing to scientific journals tied to political interest groups such as the American Cancer Society, which has financial ties with the makers of mammography equipment 16 , Due to conflicts of interest, the research being used to develop recommendations for mammography screening protocols is biased and is not a true representation of the efficacy of mammography for reducing breast cancer mortality.
This has had a large-scale impact on the development of mammography screening programs In a survey of U. However, based on U. Research also shows that women who are better informed about the risk of overdetection and overdiagnosis of breast cancer associated with mammography screening are less likely to participate in mammography screening Surveys indicate that women want to have balanced information and share the decision with their physician when it comes to whether or not they choose to go through screening mammography.
However, many women have reported that they were never provided with information on the drawbacks of mammography, such as the risks of overdiagnosis, unnecessary cancer treatment, excessive radiation exposure, and potential for causing tumor rupture.
The American Cancer Society breast cancer screening guidelines emphasize that women with serious health problems or short life expectancies should discuss with their doctors whether they should continue having mammograms.
Our guidelines also stress that age alone should not be the reason to stop having regular mammograms. A fast-growing or aggressive cancer might have already spread. Screening mammograms can often find invasive breast cancer and ductal carcinoma in situ DCIS, cancer cells in the lining of breast ducts that need to be treated. Finding and treating cancers that would never cause problems is called overdiagnosis.
These cancers are not life-threatening, and never would have been found or treated if the woman had not gotten a mammogram.
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