Breast cancer is the most frequently diagnosed cancer besides melanoma among women in the United States. It can be a very serious condition, often requiring radiation therapy, chemo therapy, hormone therapy, and even surgery in advanced cases. It is also the second leading cause of cancer death in the country (Nelson et al. , 2009). It is projected that over 232,000 women in the United States will be diagnosed with breast cancer in 2013 alone (U. S. Department, 2012), and an estimated 39,620 people will die from breast cancer this year.
Breast cancer begins on a cellular level. When cells divide too quickly or don’t die when they should it can create a build-up called a lump or mass. Not all of these masses are dangerous; they can be either malignant, or benign. The most common type of breast cancer is ductal carcinoma in situ – DCIS. This cancer begins in the breast ducts. Approximately 7 out of 10 women diagnosed with breast cancer will be diagnosed with DCIS (U. S. Department, 2012). The second most common breast cancer is lobular carcinoma, which begins in the smaller lobules of the breast.
Figure 1 shows the anatomy of the breast for reference to the ducts and lobules. Figure 1. Reprinted with permission from the National Cancer Institute website. Note: Adapted from the NCI website (2012). Screening mammography is currently the most common method of early detection of breast cancer in the United States and most developed countries world-wide (U. S. Department, 2012). The universal mammography compression system was patented in 1986 by Patrick Penetta and Jack Wennet, and it has been gaining popularity ever since.
A screening mammogram usually consists of a two-view x-ray of each breast, which is then sent to a radiologist to be interpreted. Catching breast cancer in early stages and thereby prolonging life expectancy is the primary rationale for screening mammography. Starting screening at age 40 is an attempt to jumpstart this process (Armstrong, Moye, Williams, Berlin, & Reynolds, 2007). In 1997, the National Cancer Institute, a sub-group of the National Institute of Health, constituted guidelines for women regarding screening mammography.
Although the NCI didn’t initially support screening in women aged 40-49, they changed their guidelines to include this age group in this conference. Many researchers are in support of these guidelines. However, there are a number of healthcare professionals who are unsure that the benefits of early screening outweigh the negative implications (e. g. Jorgensen and Gotszche, 2009; Kalager, Adami, Bretthauer, Tamimi, 2012). Screening mammography has alarming side effects including over-diagnosis, false-positives, false-negatives, and complications from consistent exposure to radiation.
As a result, more and more healthcare professionals are recommending that patients postpone their screening until they are at least 50 years of age. Others believe in the use of a comprehensive system to individualize benefit vs. risk on a patient to patient basis (Armstrong, Handorf, Chen, & Bristol Demeter, 2013). Still others maintain that any life-saving benefit justifies risks (Hendrik & Helvie, 2011), or even that the “risks” at all are negligible (van Ravestevn et al. , 2012). The NCI and ACS guidelines are among the most widely accepted codes in United States with regards to standard medical practices.
As such, these corporations are charged with providing the safest information to the public. This report will review the prominent positions on screening and ultimately contend that because screening mammography is unreliable, financially inefficient, and potentially harmful, women age 40-49 should be discouraged from screening. Current Screening Recommendations There are three leading groups in the United States that have guidelines established regarding screening mammography. These groups are the NCI and ACS, as mentioned previously, and the U. S. Preventative Services Task Force(USPSTF).
Currently, the USPSTF is the only one of these that does not recommend screening mammography for women under the age of 50 unless they are at an increased risk for breast cancer. They also recommend that women who are of age screen biannually instead of annually. In addition, the USPSTF is the only group who doesn’t support the screening of women over the age of 74, citing that there isn’t enough scientific evidence to prove that it is effective at decreasing mortality from breast cancer for women in this age group (Nelson et al. , 2009).
Increased Breast Cancer Risk Many factors contribute to a particular persons risk for developing breast cancer. Clearly, being a woman is the most prevalent risk factor for breast cancer. Less that 1% of breast cancer overall occurs in men (U. S. Department, 2012). Other innate risks include family history of breast cancer, race, age, and genetics. Genetics has become a particular concern in the last several years with the discovery of two genes – BRCA1 and BRCA2 that greatly increase a person’s risk for breast cancer. Additional risk factors include lifestyle choices such as weight, alcohol consumption, smoking, and diet (Armstrong, 2013).
Once a person has been judged to be at an increased risk for acquiring breast cancer before the age of 50, many healthcare professionals will recommend that the patient submit to mammography screening earlier and more frequently than their average-risk counterparts (Grady, 2009). Background and Overview of Screening Mammography A screening mammogram is typically a two-view x-ray of each breast; one from the side, and one from above. It is taken while the breast is compressed between an x-ray plate and a plastic plate. The compression spreads the fat tissue in the breast, making the x-ray easier to read.
There are two different kinds of mammograms, “film” and “digital. ” Traditional film mammography utilizes the basic x-ray film that has to be developed into a negative and viewed in front of a bright light. Digital mammography transmits a clearer image than traditional mammography directly onto a computer. There are several abnormalities that screening mammograms are used to detect. Masses or lumps can be detected with mammograms even before they are large enough to be seen or felt either by breast self-examination (BSE) or clinical breast examination (CBE).
The other major abnormality that a mammogram can detect is called a calcification, a calcium deposit in the breast that appears as a white spot on a mammogram. Macrocalcifications are large calcium deposits that frequently come with age. Microcalcifications are small specks of calcium that are often a sign of quickly dividing cells, and therefore a sign of potential cancer (U. S. Department, 2012). To streamline the process of reading mammograms, the ACS has developed a fixed method for radiologists to use to classify mammogram findings. This system is called BI-RADS. It includes seven categories, each one with a specified follow-up plan.
Film Mammography Film mammography was first conceptualized by Albert Saloman, a German surgeon, in 1913. It wasn’t developed into a specific, all-inclusive machine until Panetta and Wennet patented it in 1986. This development allowed physicians to see breast masses that could not be felt with a typical CBE. Film mammography requires that a cassette be placed below the breast. The breast is then compressed with a plastic plate and a low-dose radiation x-ray is taken. The x-ray dose is the same for every patient, and therefore high breast density can extensively lower the quality of the mammogram (Dershaw, 2006).
Digital Mammography Digital mammography was first introduced in 2001, and although there is currently no indication that digital screening is more accurate than film screening, it has many benefits. Digital screening provides a sharper image, records the x-ray directly onto a computer – streamlining the process of reading the mammogram for the radiologist, and also has the capability to deliver varying levels of radiation, making it easier to get a readable x-ray on women with particularly dense breasts.
Premenopausal women are especially good candidates for digital mammography because they typically have denser breasts than women who have reached menopause (Dershaw, 2006). Figure 2 illustrates the difference in quality of a film mammogram in comparison to a digital mammogram. Figure 2. Comparison of film mammogram (left) and digital mammogram (right). Image reprinted with permission from the University of Maryland Medical Center. Additional Screening Methods Digital and Film screening are the most popular methods of detecting breast cancer in the United States.
MRI and Tomography are also used, but they are not as common and screening mammography. These methods will not be considered in this report as the main focus is on the safety and effectiveness of screening mammography. Risks of Screening Mammography Mammography is a far from perfect procedure. Although it has been proven to reduce the mortality rate for women age 40-74 (Armstrong, 2007), it does not come without a price. Many women undergoing a screening mammogram express that the breast compression is painful, there is anxiety regarding long wait time for screening results, and concern about the costs of screening and follow-up.
There are several concerns that have gained a significant amount of attention over the years. Included among these are increased risk of cancer due to radiation exposure, long-term effects of false readings, and high rate of over-diagnosis. Balancing Risks vs. Life Saving Benefit of Screening Despite the concerns, many individuals are still in support of the ACS and NCI’s current guidelines; encouraging women to start screening mammography at age 40 and continue annually for as long as the woman is in good health (U. S. Department, 2012; American Cancer, 2012).
Some of the most poignant arguments in favor of the current guidelines will be discussed in the following pages, followed by an analysis of the positions. Negligible Risk Claim This position argues that the risks of screening mammography are trivial at best. Most proponents of this argument claim that there is currently not enough research to suggest that there are long-term negative impacts of screening mammography. For example, van Ravestevn et al. (2012) conducted an original research program in which the harm-benefit ratio of screening mammography was assessed. Their assessment of the harm-benefit ratio found that women of all ages had relatively low risk of negative consequences from screening mammography.
The study encourages women 40 and over to begin biannual screening, especially women who have an increased risk of breast cancer. In another study de Gelder, Draisma, Heijnsdijk, and de Koning (2011) measured the risks of radiation induced breast cancer vs. the life-saving benefit and found the life-saving benefit to be significant enough to “negate” concerns over radiation induced cancer. They also point out that while high-dose radiation has been proven to contribute to development of cancer, low-dose radiation has not been.
De Gelder et al. concludes with stating that any concern about radiation-induced cancer is speculative, and that other factors contributing to cancer aren’t addressed in the studies currently available. Refutation of Negligible Risk Claim Exposure to radiation has long been a topic of concern with regards to mammography. While many scientific researchers (e. g. de Gelder et al. , 2011) are still calling the research “inconclusive,” it has been stated time and time again that radiation risk increases with higher doses of exposure, younger age at exposure, and longer-follow up (Armstrong, 2007).
For quite some time, it has been postulated that the premenopausal breast is highly sensitive to radiation (Epstein, 2001). In addition, it is highly possible that exposing the same amount of radiation we would use for a chest x-ray on a much smaller area causes the RAD – radiation-absorbed dose – to be much higher. This is a particular problem for women with above-average risk for developing breast cancer because they are frequently encouraged to start screening earlier, and to get mammograms more often than average risk women.
In a recent study conducted by Frankenburg-Schwager and Gregus (2012) on women with and without the BRCA mutation it was shown that low-dose radiation causes the DNA to fragment and interferes with its ability to repair itself, resulting in gross chromosomal rearrangements and aneuploidy. Chromosomal rearrangements and aneuploidy – an in complete chromosome set, are frequently observed in breast cancer cells. This study suggests that the very women that we have been encouraging to screen early and often are the same women who are most likely to have an increased risk of breast cancer from exposure to radiation (Grady, 2009).
Epstein (2001) even suggests a 1% increase in the probability of acquiring breast cancer for every mammogram exposure. This translates to an extra 10% risk of breast cancer for women who start annual screening at forty instead of 50. Decreased Mortality Claim Perhaps the most prolific of claim supporting screening initiation at age 40 is the decreased mortality claim. It has been proven by many that despite possible risks, breast cancer mortality is reduced by screening mammography starting at 40 years of age (e. g. Armstrong, et al. 2007; Nelson, et al. , 2009; National Institute, 1997).
This group argues that the life-years gained from screening mammography justify any risks. Hendrik and Helvie (2011) authored an analysis responding to the USPSTF’s choice to change the recommended age to initiate screening from 40 to 50 years of age. This analysis criticizes the USPSTF’s method for scrutinizing studies for several reasons, among these are concerns that the USPSTF omitted too many studies where screening mammography’s improvement over time was highlighted –of 514 studies they only used 112 as reference for the update, that the cost-effectiveness of screening mammography vs. other accepted alternatives wasn’t considered, and that screening mammography’s impact on decreasing breast cancer’s mortality rate was severely understated.
The study concludes that screening mammography decreases breast cancer mortality by 36. 9%, and that therefore women should start screening at 40 because if false-negatives are one of the greatest harms of screening, then advising against screening is doing more harm because it’s missing all of them. Refutation of Decreased Mortality Claim
False-positive and false-negative mammograms are perhaps the most under-advertised problem with screening mammography (Reynolds, 2012). Reynolds suggests that mammograms are all too frequently marketed as an infallible method for detection of breast cancer. This is not the case. False-positives are incidences where mammograms come back abnormal, require further testing, and there is nothing wrong with the breast. False-negatives occur when a screening mammogram fails to detect a malignant mass even when one is present.