The American Cancer Society published a breast cancer screening guideline that steers toward the middle course in deciding when mammography screening should start and how often it should be performed.
- The ACS guideline now says 45 is a good age to get the first mammogram. In the past, the society recommended starting at 40. The U.S. Preventative Services Task Force gives a “C” rating to screening before age 50 (The Cancer Letter, April 24).
- Repeating mammograms every other year after age 55 is acceptable, the society now states. In the past, the society recommended annual mammography screening. USPSTF said screening should be biennial after age 50.
By steering toward the middle, the society triggered the ire of both the proponents of starting mammography at 40 and the proponents of starting at 50. On top of that, the guidelines caused consternation among supporters of annual screening and, predictably, from representatives of subspecialties that perform screening.
The ACS breast cancer screening guideline, which was published in JAMA Oct. 20, is important because it’s the first to utilize pre-specified guideline-making procedures published in the same journal in 2011. The ACS guideline-making group commissioned a systematic review of the evidence by an independent center, the Duke University Evidence Synthesis Group.
“We recommend that a woman who understands that her risk for breast cancer is low in the early part of her 40s, but who places high value on doing everything she can to reduce mortality—even though her risk is low, and her risk of a false-positive is higher in her early 40s—may opt to start screening before age 45; whether it’s 40, 41, or 42,” said Richard Wender, chief cancer control officer at the American Cancer Society.
A conversation with Wender appears on p. 5.
Berry: “Arbitrary Starting Age”
“Breast cancer screening is all about uncertainty,” said Donald Berry, professor of biostatistics at M.D. Anderson Cancer Center and co-founder of Berry Consultants, a statistical consulting company specializing in the Bayesian approach to medical statistics. “The benefits and risks of mammographic screening have been discussed ad nauseam. Both are uncertain but we know rather more about the risks. In terms of benefits, we have no idea at what age women should start screening or end screening, or if they should start at all.
“We know that breast cancer mortality in the U.S. population decreased by a third between 1990 and 2010. That is huge! It is due to some combination of widespread screening and advances in treatment.
“Treatment advances is probably the bigger contributor but its relative contribution is uncertain. The randomized screening trials were conducted mostly before the use of modern therapy. Perhaps modern therapies make screening redundant, or perhaps finding cancers early enhances the benefits of therapy. We don’t know which.
“The new ACS guidelines are great, and for two reasons. First, they stress choice. Second, they come down between the recommendations of other groups. Both of these should convey to women that we just don’t know what to recommend.
“The ACS age cutoff of 45 between ‘choice’ for 40-44 and ‘should get’ annual mammograms for 45-54 is curious. A ‘follow-up analysis’ in a 2002 pooling of the Swedish randomized trials showed a 15 percent reduction in breast cancer mortality in the former group and only a 7 percent reduction in the latter group. The Canadian randomized trials showed no mortality reduction in either group. Moreover, there’s no empirical evidence that annual screening is better than biennial screening for women 45-54, or in any other age group for that matter.
“Rather than picking an arbitrary starting age the most honest recommendation we can make to women is that we don’t know what to recommend. We should help them understand why that is so by communicating in an unbiased fashion the pros and cons of screening depending on age…and the associated uncertainties.”
In an editorial in JAMA Internal Medicine, Karla Kerlikowske, of San Francisco Veterans Affairs Medical Center, wrote that “while the new ACS guidelines provide the opportunity to reduce screening harms, they have little added benefit in reducing lifetime risk of breast cancer death compared with the USPSTF guidelines because most of the benefit of mammography screening results from screening women aged 50 to 74 years, when breast cancer incidence and mortality are highest and mammography most efficacious.”
In another JAMA editorial, Nancy Keating, of the Department of Health Care Policy at Harvard Medical School, and Lydia Pace, of the Division of Women’s Health at Brigham and Women’s Hospital, noted that the ability of mammography to save lives is modest. Thus, a better test would do more to reduce mortality than seeking greater utilization of mammography.
“For women in their 40s and 50s, randomized trial evidence suggests that screening mammography modestly decreases breast cancer mortality by approximately 15 percent,” Keating and Pace wrote. “Thus, about 85 percent of women in their 40s and 50s who die of breast cancer would have died regardless of mammography screening. Moreover, because the risk of breast cancer is low for women in their 40s and to some extent women in their 50s, the modest relative benefit of 15 percent translates to a very small absolute benefit (approximately 5 of 10,000 women in their 40s and 10 of 10,000 women in their 50s are likely to have a breast cancer death prevented by regular mammography).
“Especially for average-risk women, decisions to undergo regular mammography screening must also consider the harms of mammography—most notably the possibility of overdiagnosis and resultant overtreatment (age-specific estimates of which are lacking) and also the risks of false positives and unnecessary biopsies (known to be greater in younger women and women screened more frequently).
“Ultimately, better screening tools are needed. The future of breast cancer screening is likely to entail a more personalized understanding of breast cancer risk, one that incorporates both published risk assessment tools using combinations of known risk factors with newer techniques such as genomics. If women who are at higher risk of aggressive breast cancer could be more accurately identified, for example, it would be possible to more definitively identify those women who are most likely to benefit from earlier and more frequent breast cancer screening and less likely to experience the related harms.”
The ACS guidelines recommend:
- All women should become familiar with the potential benefits, limitations, and harms associated with breast cancer screening.
- Women with an average risk of breast cancer should undergo regular screening mammography starting at age 45 (strong recommendation*)
- Women who are 45 to 54 years should be screened annually (qualified recommendation**)
- Women who are 55 and older should transition to biennial screening or have the opportunity to continue screening annually (qualified recommendation)
- Women should have the opportunity to begin annual screening between the ages of 40 and 44 (qualified recommendation)
- Women should continue screening as long as their overall health is good and they have a life expectancy of 10 years or more (qualified recommendation)
- The ACS does not recommend clinical breast examination for breast cancer screening among average-risk women at any age (qualified recommendation)
*A strong recommendation conveys the consensus that the benefits of adherence to that intervention outweigh the undesirable effects that may result from screening.
**Qualified recommendations indicate there is clear evidence of benefit of screening but less certainty about the balance of benefits and harms, or about patients’ values and preferences, which could lead to different decisions about screening.
Guidelines Get No Applause
The National Breast Cancer Coalition, which has been consistently skeptical about the role of mammography, said that although the new guideline moves closer to being evidence-based, it will not help women.
“The guidelines are a slight change from past ACS positions,” NBCC President Fran Visco said in a statement. “While we at the National Breast Cancer Coalition appreciate that ACS is moving closer to the weight of the scientific evidence and in the direction that the data support, we do not believe this new interpretation of the data will in fact help women.
“The never ending discussion over mammography screening and the issuing of multiple screening guidelines only adds to the confusion for healthy women who want to make informed decisions. Both the2015 U.S. Preventive Services Task Force Draft Guidelinesand thenew ACS mammography screening guidelines recognize that the strength of the scientific evidence for a reduction in mortality by screening, if any, is modest at best. And it is non-existent for most women.
“No matter how we parse groups into screen or not, use five-year or 10-year increments for guidelines, or start at age 45 or 50, mammography screening will not have a major impact on breast cancer mortality. But it does take up most of the conversation about breast cancer. It is time to become aware of the fact that 40,291 women in this country and more than half a million women around the world will die of breast cancer this year and that number is projected to be 846,587 by 2035. And even if we screen all women, those numbers will not significantly change.
“Let’s stop spending so much time on the issue of screening and focus instead on how to stop women and men from getting breast cancer in the first place, prevent its spread and stop deaths from breast cancer. We need to identify what makes a breast cancer tumor lethal so that when tumors are detected there will be no question about whether or not to treat it. Nonlethal tumors will no longer be treated with unnecessary and even harmful interventions. Let’s focus on the areas of research that will help us reach those goals. It is within our power to know how to do these things…if we shift our focus and change the conversation to ENDING breast cancer.”
The Susan G. Komen breast cancer organization said that the continuing debate over the timing of mammography fails to address several important issues.
“Although guidelines may differ regarding the age at which routine screening should begin, there is agreement that mammography is the best available tool for detecting breast cancer and that women and their health care providers should decide when those screenings should begin for individuals,” said Judy Salerno, president and CEO of Susan G. Komen.
“First, the medical field is moving toward determining individual needs for screening based on a woman’s risk, such as family history of breast cancer. Ultimately, women must have better and more accurate information about their individual risk for breast cancer so that they and their providers can make informed decisions about the screening schedule that is right for them.
“Second, it is estimated that about one-third of women who should be screened do not access these services. This means that we must take all steps necessary to ensure that women don’t face economic or other barriers when their health care providers recommend screening. It’s well established that early detection, combined with effective treatment, reduces mortality from breast cancer.
“Third—and this is a point we’ve made often—we absolutely must continue to invest in finding screening methods that are more accurate, cost-effective, easy-to-administer, and more widely available than mammography.”
The American College of Radiology and Society of Breast Imaging said they continue to recommend that women get yearly mammograms starting at age 40.
“The new ACS guidelines show that if a woman wants to reduce, as much as possible, her risk of dying of breast cancer, she will choose yearly mammography starting at age 40,” said Debra Monticciolo, chair of the American College of Radiology Breast Imaging Commission.
“A recent study in the British Medical Journal confirms this, showing that early detection of breast cancer is critical for improving breast cancer survival, regardless of therapy advances. Moving away from annual screening of women ages 40 and older puts women’s lives at risk.”
ACR and SBI said concerns about overdiagnosis are “vastly inflated.”
“Published research shows that nearly all women who experience a false-positive exam endorse regular screening and want to know their status,” said SBI President Elizabeth Morris. “The ACR and SBI agree with ACS that women 40 and older should have access to mammograms. We also recommend that women, 40 to 45, get screened and would expect that mammography critics would agree that Medicare and private insurers should be required to cover women 40 and older for these exams.”
House Reps. Renee Ellmers (R-N.C.) and Debbie Wasserman Schultz (D-Fla.) said the discrepancies between the American Cancer Society and the USPSTF guidelines make it urgent to set aside implementation of the task force guidelines for two years, to allow scientists to sort out the differences. The two are co-sponsors of H.R. 3339—the Protect Access to Lifesaving Screenings Act
Said Ellmers: “Given the variance in screening recommendations among women’s health groups and cancer organizations, I think it has become increasingly apparent that my current bipartisan legislation, H.R. 3339, the PALS Act, should swiftly move through the House of Representatives in order to eliminate barriers for patients seeking access to early intervention through life-saving screenings.
“The PALS Act advocates for a two-year freeze on current proposed USPSTF guidance [sic] so that providers, patients and lawmakers can address the differing recommendations for breast cancer mammography screenings. A two-year moratorium would pause implementation of the USPSTF’s breast cancer screening recommendations and would assist in eliminating additional confusion for women who are seeking clarification on when and how often to receive mammograms.
“I will continue working with my colleagues to advocate for the PALS Act so that we can ensure millions of women, young and old, have the resources and tools that they need in order to detect and defeat breast cancer.”
Said Wasserman Schultz:
“These new guidelines should not discourage young women from taking control of their breast health and being their own advocates with their health care providers.
“Between these recommendations, the draft recommendations from the U.S. Preventive Services Task Force earlier this year and the recommendations of the Association of Obstetricians and Gynecologists, there is clearly ongoing debate about when individual women should begin mammograms. What is certain is that women must have the information and tools they need to understand the role mammograms have in their overall breast health.
“That is why we joined forces to introduce the Protecting Access to Lifesaving Screenings Act, H.R. 3339, which would place a two-year moratorium on implementing the USPSTF breast cancer screening recommendations. This two-year ‘time out’ would provide ample time for a thoughtful discussion about whether changes need to be made and how those changes will impact insurance coverage for women in their 40s. Insurance companies will be monitoring both the USPSTF and ACS guidelines closely, and it is essential for us to make sure that we have proper financial protection for women who need it for mammogram screening.
“The differing recommendations are confusing for women. That is why this moratorium is absolutely necessary. Without it, many women who need earlier screenings may not catch their cancer at its earliest onset.
“These new ACS guidelines also underscore that we must continue to empower young women with the tools, resources and information they need to detect, prevent and beat this deadly disease.”
In another reaction, a young cancer survivor launched a Change.org petition urging ACS to retract the guideline.
“I was diagnosed with breast cancer on Nov. 11, 2014 at the age of 35, with no family history, no breast cancer gene, no symptoms, and no lumps. I asked for a mammogram and thankfully my GYN sent me and it was caught EARLY with a mammogram and ultrasound,” the petitioner wrote. “If I waited until I was 40 years old, it would have been invasive and hard to treat.”
There is no guideline that calls for mammography screening of asymptomatic 35-year-old women with no known risk factors.
