Last winter, the United States Preventive Services Task Force (USPSTF) updated its 2002 recommendations for screening mammography in women ages 40-49. The USPSTF also recommended that women under 40 should not be screened for breast cancer except under special circumstance. The USPSTF went on to recommend that women under 40 should not do self-breast exams (SBE) and that women under 40 should not be examined by their primary care physician for breast cancer, i.e. clinical breast exam (CBE).
The update included the following recommendations:
- USPSTF recommends against routine screening mammography in women ages 40 49;
- USPSTF recommends against teaching women how to perform BSE;
- USPSTF concluded that current evidence is insufficient to assess the additional benefits and harms of the CBE beyond screening mammography in women 40 years or older.
The new recommendations were based on information and statistics gathered from a structured literature search and meta-analysis of randomized controlled trials of breast cancer screening. Studies using mammography (film and digital), MRI, CBE, and BSE with breast cancer mortality outcomes published since 2001 were reviewed.1 Additionally, the USPSTF searched for updates to previously published trials that were used for their 2002 recommendation. Based on pre selected criteria, the USPSTF determined that a total of 8 trials provided data for the updated recommendation (updates to 1 study used previously and 1 new study). One of the studies dated back to 1963, while the others studies took place between the years of 1976 1982.
Clearly, one of the major problems with this meta-analysis is that the most recent trial that was included began in 1991 and the other trials began years earlier. The one “new” trial selected in the USPSTF’s analysis was the Age trial. This trial enrolled women from the United Kingdom, between the ages of 39-41, and the participants were then followed until age 48. Additional information came from a new publication based on results from a Swedish study that began in 1982!
Let’s discuss the Age trial that began in 1991. This study provided the largest number of control subjects for the analysis (106,956). The quality of this study was rated as ‘fair’ by the USPSTF due to the contamination in the groups not being described and 70% or fewer women attending screening across the trial.1 Furthermore, the USPSTF stated in their report that: “Also, its applicability to women in the United States is not clear, in light of important differences between mammography screening practices in the United States and United Kingdom.”
I have a hard time understanding how recommendations were made based on data from the early 1990s and from a country that has a different standard of care for screening mammography practices and other data that dates back into the 1960s.
Only 2 of the 8 trials selected for the analysis were conducted in North America. The USPSTF also failed to take into account the current trends of digital mammography and MRI. The USPSTF found that no trials have been published that evaluated the effectiveness of digital mammography or MRI in average-risk women.1 Antiquated data, differing standards of care, new technologies, did not however stop the USPSTF from moving forward and making recommendations that could adversely affect the lives of millions of women in the United States.
One thing I found surprising is the only number that has seemingly changed between the meta analysis conducted in 2002 and the meta analysis performed in 2009 is the number of screenings performed to prevent 1 breast cancer death. In the 2002 meta-analysis this number was 1792; in 2009 the number had increased to 1904.
Noteworthy is that in 2002, the USPSTF also provided the results when a Canadian study was excluded from the meta-analysis due to cited problems with the study. In 2002, without the Canadian study, the numbers decreased to 1385 screenings needed to prevent 1 breast cancer death. No such analysis was provided in the 2009 update.
In 2002, the USPSTF stated that there was no evidence that the BSE or CBE reduced breast cancer death rates. Needless to say, the flip side to this conclusion is that here is no evidence that BSE or CBE doesn’t’ reduce breast cancer deaths. One fact that is known is that BSE and CBE have in the past, and will in the future, identify some breast cancers. And in some instances, these early findings will lead to diagnosis, treatment and lives saved.
In 2009, the USPSTF recommend against teaching women how to perform a BSE. A study conducted in Russia, one which the USPSTF used as part of their recommendation, showed a “significant increase in the number of cases of breast cancer detected when BSE instruction was provided, however there was no reduction in all-cause mortality.”1
The USPSTF concluded that current evidence is insufficient to assess the additional benefits and harms of the clinical breast examination (CBE) beyond screening mammography in women 40 years or older. So, the USPSTF decided to get rid of CBE, currently a standard of care, based on what they describe as insufficient data.
Logic might lead some to conclude that even though the benefits of SBE and CBE cannot be quantified, lives are saved and exams should continue. This is true especially in women who are younger than 40, like my friend’s 37 year old daughter. Also, when breast cancer does occur in this younger group the results can be especially devastating. This sort of logic clearly did not play into the USPSTF’s recommendation.
To recap, the USPSTF cites a study, which demonstrated increased detection of cancer cases with SBE, the USPSTF concludes there is insufficient data to quantify the benefits, SO the USPSTF concludes women should not be taught BSE or given CBE.
Frankly, it appears to me that the USPSTF had a preconceived conclusion they were working toward before the analysis was even conducted and whatever the motivation for that conclusion was, it was not the improvement of healthcare or saving lives.
In addition to the USPSTF, there is another Federal Agency with over 50 years of experience making decisions that directly affects America’s healthcare. That Agency is, of course, the US Food and Drug Administration. Certain standards have evolved over the last half-century that the FDA expects (requires) for studies to be considered acceptable to be used for critical decision making that will affect the health and well being of US citizens. Some of these standards include such reasonable requirements as:
- The data must reflect current standard of care in the United States;
Clearly, the USPSTF have no such standards and adhered to none of the FDA standards described above. It just seems wrong to me that such a task force can make sweeping recommendations affecting the quality of healthcare in the United States and not be held to similar standards that pharmaceutical, biotechnology and medical device companies are held to when getting a new product into our healthcare system.
According to breastcancer.org, breast cancer incidence in women in the United States is 1 in 8 or roughly 13%. By age 30, approximately 1 in 229 women will develop breast cancer in the next 10 years, and by age 40, 1 in 68 women will develop breast cancer. (Source: American Cancer Society Breast Cancer Facts & Figures, 2005-2006.)
With those numbers in mind, I want to stress that I agree that large epidemiological studies can be extremely important to guide some healthcare decisions. But, at the same time, when decisions are made that will affect the lives and health of thousands to millions of people, an element of common sense needs to prevail. In light of the USPSTF recommendations, the questions still remain: Why shouldn’t we be encouraging women to perform self breast exams; why shouldn’t physicians continue doing clinical breast exams? I believe the data used by the USPSTF is outdated and based on old imaging standards and any recommendations based on that data are ill advised and should not be followed.
[1] Nelson HD, Tyne K, Naik A, Bougatsos C, Chan BK, Humphrey L. Screening for breast cancer: an update for the U.S. Preventive Services Task Force. Ann Intern Med. 2009 Nov 17;151(10):727-37.
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