Taken from the January/February 2010 issue of the Women's Health Activist Newsletter.
The U.S. Preventive Services Task Force (USPSTF) recently released new guidelines recommending against routine mammograms for women aged 40-49, and recommending screening every two years for women 50-74.1 We agree with these perfectly rational, evidence-based recommendations, brought to you by a formerly obscure panel of preventive medicine experts appointed (but not employed) by the U.S. Agency for Healthcare Research and Quality.
Network members have long known that there is little evidence supporting routine mammograms for women in their 40s. Mammography is much less accurate in pre-menopausal women, who have denser, more biologically active breast tissue than postmenopausal women, whose breasts have more uniform fatty tissue. Screening mammograms miss cancers and raise false alarms more often in younger women. That doesn’t mean mammograms should never occur in this age group, but as a routine screening test, mammograms aren’t precise enough to recommend to all women in their 40s.
Yet, the new guidelines generated an immediate outcry. Reuters quoted Carol H. Lee, chair of the American College of Radiology Breast Imaging Commission, saying they “place a great many women at risk of dying unnecessarily,’ and Daniel Kopans, a Harvard radiologist, saying they would “condemn women ages 40 to 49 to unnecessary deaths from breast cancer” and were “scientifically unjustified.”2 Some critics accused the USPSTF of trying to save the government money. That’s ridiculous; USPSTF members are carefully vetted for conflicts of interest. No panelist would benefit financially, and costs aren’t considered when the USPSTF considers evidence. Perhaps the charge was meant to deflect attention from the critics who have very real conflicts of interest. Curiously, no mainstream publication has mentioned these.
It has been depressing to see some health activists on the wrong side of the evidence. Otis Brawley (a physician who used to be an admirably outspoken defender of evidence and public health) appears to have transformed since becoming the American Cancer Society’s (ACS) chief medical officer. On October 21, he told The New York Times, “The advantages to screening have been exaggerated.” Five days later, in a stilted letter to The Washington Post, he wrote that the earlier article “indicates that the American Cancer Society is changing its guidance on cancer screening to emphasize the risk of over-treatment. We’re not.” And, “It would be tragic if this article led women 40 and over to question the value of getting a mammogram.” Three weeks later, he published an op-ed that stating the ACS will continue to recommend screening for women starting at 40, and that the USPSTF “took a step backward in the fight against breast cancer.”3 (You can practically feel his arm being twisted.)
It’s not hard to see why the ACS was upset by Brawley’s original quote. Donors to ACS Cancer Action Network, the “nonprofit, nonpartisan advocacy affiliate of the American Cancer Society”, include Hologic, which makes breast imaging products, and Johnson & Johnson, which makes an image-guided breast biopsy product.
The industry-funded organizations and doctors who seemed so concerned about preserving women’s lives through mammography sure are silent about the inconvenient truth that mammograms use X-rays and are known to increase the lifetime risk of breast cancer. Radiation risks are cumulative and of most concern in younger women, who have more time to develop cancer. Radiation was once used to treat tuberculosis, benign breast disease, and even breast inflammation (mastitis); women who had radiation treatment had higher breast cancer rates decades later.4 A meta-analysis of 6 studies of 9,420 women at high-risk of developing breast cancer (due to BRCA1 or BCRA2 gene mutations or a family history of breast cancer) found that having five or more mammograms increased the cancer risk 2.5-fold.5
A case-control study in 1,742 women with breast cancer under age 50 found that, compared to 441 controls, multiple mammograms five or more years prior to diagnosis almost doubled the woman’s breast cancer risk.6 A U.K. study estimated that annual breast cancer screening starting at age 40 would increase radiation-induced breast cancer mortality by 0.5 per 100 women screened.7 That’s five times the increase in radiation-induced breast cancer mortality when annual screening started at age 50 (0.11 per 100 women screened). A German study that calculated the ratio of lives saved to deaths caused by screening mammography found that the excess lifetime risk of radiation-induced breast cancer when screening mammography was started at age 40 was more than triple the risk, compared to starting screening at age 50.8
How many lives are saved by mammography? One analysis indicates that mammography can be credited for saving the lives of 4.3% of women with breast cancer detectable by mammography. Over 15 years, 99.29% of women over 50 who were screened will be alive, versus 99.12% who were not screened.9 We still think screening mammography is definitely beneficial in women over 50 because it detects far more cancers than it causes, and treating cancers in this age group lengthens lives.
Many questions remaining about the connection between mammograms and cancer risk. Just because the risk is difficult to estimate doesn’t mean it should be ignored. Benefits still outweigh the risks for women over 50 but, if we’re going to protest something, how about demonstrating in favor of researching breast cancer detection techniques that don’t cause cancer?
Charlea T. Massion, MD, is a practicing physician in Santa Cruz County specializing in hospice and palliative care. Charlea brought her passion for improving women’s health along with 40+ years of health care experience to the NWHN as a member of the board for 8 years. She also co-founded the American College of Women’s Health Physicians.
Adriane Fugh-Berman, MD, is a former NWHN Board Chair whose research presents a critical analysis of the marketing of prescription drugs. Adriane educates prescribers on pharmaceutical marketing practices as Director of the PharmedOUT program, and created the Health in the Public Interest program at Georgetown University School of Medicine where she trains a new generation of consumer advocates.
The continued availability of external resources is outside of the NWHN’s control. If the link you are looking for is broken, contact us at [email protected] to request more current citation information.
Part of this article was based on “Mammography and the Corporate Breast,” by Dr Fugh-Berman and Alicia M. Bell, published in Bioethics Forum: http:// www.thehastingscenter.org/Bioethicsforum/Post.aspx?id=4194.
1. U.S. Preventive Services Task Force, “Screening for breast cancer: U.S. Preventive Services Task Force Recommendation Statement”, Ann Int Med 2009; 151;716-26; and Nelson HD, Tyne K, Naik A, et al., “Screening for breast cancer: an update for the U.S. Preventive Services Task Force,” Ann Int Med 2009; 151:727-37.
2. Steenhuysen J. “New U.S. guidelines: routine mammograms start at 50,” Reuters, Nov. 17 2009. Accessed 11/18/09 from http://www.reuters.com/article/topNews/idUSTRE5AF5BH20091117
3. Kolata G, “Cancer Group Has Concerns On Screenings,” New York Times, October 21, 2009, Accessed from: http://query.nytimes.com/gst/fullpage.html?res= 9404E1D91431F932A15753C1A96F9C8B63; and Brawley O, “The Cancer Screening Controversy (letter)”, The New York Times, October 25, 2009, available online: http://www.nytimes.com/2009/10/26/opinion/l26cancer.html; and Brawley O, “Let’s stick with mammograms”, The Washington Post, November 19, 2009. Available online: http://www.washingtonpost.com/wp-dyn/content/article/2009/11/18/AR2009111803160.html
4. Feig SA, Hendrick RE, “Radiation risk from screening mammography of women aged 40-49 years”, J Natl Cancer Inst Monogr 1997; 22:119-24; and Shore RE, Hempelmann LH, Kowaluk E, Mansur PS, Pasternack BS, Albert RE, Haughie GE. Breast neoplasms in women treated with x-rays for acute postpartum mastitis.J Natl Cancer Inst. 1977 Sep;59(3):813-22.
5. Jansen-van der Weide MC, De Bock GH,Greuter M, et al., “Abstract RO22-04: Mammography Screening and Radiation-induced Breast Cancer among Women with a Familial or Genetic Predisposition: A Meta-analysis,” Radiological Society of North America (RSNA) 95th Scientific Assembly and Annual Meeting, Presented November 30, 2009. Available online at: http://rsna2009.rsna.org/search/event_display.cfm?em_id=8012231&printmode=y&autoprint=n
6. Ma H, Hill CK, Bernstein L, Ursin G, “Low-dose medical radiation exposure and breast cancer risk in women under age 50 years overall and by estrogen and progesterone receptor status: results from a case-control and a case-case comparison,” Breast Cancer Res Treat 2008; 109:77-90.
7. de Gonzalez AB, Reeves G, “Mammographic screening before age 50 years in the UK: comparison of the radiation risks with mortality benefits”, Brit J Cancer 2005; 93:590-96.
8. Nekolla EA, Griebel J, Brix G. “Radiation risk associated with mammography screening examinations for women younger than 50 years of age”, Z Med Phys 2008; 18(3):170-9.
9. Keen JD, Keen JE, “What is the point: will screening mammography save my life?” BMC Med Inform Decis Mak 2009; Apr 2;9:18.