The U.S. Preventive Services Task Force today released a final recommendation statement on breast cancer screening, reiterating the same guidance it offered in its last recommendation statement 7 years ago.
The USPSTF recommends biennial screening mammography for women aged 50 to 74 years. The statement also suggests the decision to start screening mammography earlier than age 50 years should be an individual one.
Albert L. Siu
“Women who place a higher value on the potential benefit than the potential harms [of screening mammography] may choose to begin biennial screening between the ages of 40 and 49 years,” task force chairman Albert L. Siu, MD, MSPH, chairman of the department of geriatrics and palliative medicine at Icahn School of Medicine at Mount Sinai, and colleagues wrote.
The USPSTF last issued a recommendation statement on breast cancer screening in 2009. For this update, an independent volunteer panel conducted an in-depth review of the evidence documenting the potential benefits and harms of screening mammography.
The task force issued an updated draft recommendation last year, then solicited input from the clinical community and the public prior to finalizing the recommendations.
“Our updated assessment of the science remains unchanged from our 2009 recommendation on mammography,” Kirsten Bibbins-Domingo, MD, PhD, vice chair of the USPSTF and professor of medicine at University of California, San Francisco said in a video released to the media through Annals of Internal Medicine, the journal in which the recommendation statement was published. “We found that mammography screening is important for helping women aged 40 to 74 reduce their risk for dying of breast cancer.”
The USPSTF’s draft recommendation and a guideline released last year by the American Cancer Society have been criticized because they differ from recommendations issued by the National Comprehensive Cancer Network, the American College of Radiology and the American Congress of Obstetricians and Gynecologists. These other entities — as well as major breast cancer centers such as Memorial Sloan Kettering Cancer Center and The University of Texas MD Anderson Cancer Center — recommend screening mammography begin at age 40 years.
The USPSTF recommendation frequently has been misunderstood, Bibbins-Domingo said.
“Our 2009 recommendation has been incorrectly interpreted as a recommendation against screening for women in their 40s,” she said in the video. “Actually, the 2009 recommendation — and this updated scientific report — found evidence that supports a wide range of screening choices.”
The final USPSTF recommendation for biennial screening mammography among women aged 50 to 74 is designated as a “B” recommendation, which means the task force concluded there is “high certainty that the net benefit is moderate, or [that] there is moderate certainty that the net benefit is moderate to substantial.”
The final recommendation that addresses how women in their 40s should approach screening is designated as a “C” recommendation, which means the task force recommends “selectively offering or providing this service to individual patients based on professional judgment and patient preferences.”
Some critics have characterized this as a recommendation against screening, but task force members clarified the definition of a “C” recommendation in their final statement.
“[It] is not a recommendation against mammography screening in this age group,” Siu and colleagues wrote. “It signifies moderate certainty of a net benefit for screening that is small in magnitude. A ‘C’ recommendation emphasizes that the decision to screen should be an individual one, made after a woman weighs the potential benefit against the possible harms.”
Those harms include false positives and unnecessary biopsies, Bibbins-Domingo said.
“All women who undergo regular screening are at risk for the diagnosis and treatment of noninvasive and invasive breast cancer that would otherwise not cause them harm during their lifetime,” she said.
Women in their 40s who have a first-degree relative with breast cancer may derive greater benefit than average-risk women from initiating mammography screening prior to age 50 years, the task force emphasized.
A federal law passed shortly after the USPSTF issued its 2009 recommendation required private insurance companies to cover procedures that the task force graded as “A” or “B” recommendations. An exception was made for the “C” recommendation of screening mammography. That exception was set to expire upon the release of this task force update, meaning women younger than age 50 would not have had coverage for screening mammograms.
However, Congress passed a measure in December that included a rider that extended the mammography screening exception indefinitely.
“The target should not be the USPSTF, which cannot make payment decisions,” Christine Laine, MD, MPH, senior vice president of the American College of Physicians and editor-in-chief of Annals of Internal Medicine, and colleagues wrote in an editorial that accompanied the recommendation statement. “Congress and health plans have the option of mandating private insurance coverage or noncoverage for a grade “C” recommendation.
“We are faced once again with a question about acceptable boundaries when politics meets science,” Laine and colleagues wrote. “Instead of freezing the guidelines in time, we should eliminate coverage decisions that do not accommodate all three pillars of evidence-based health care: scientific evidence, clinical knowledge and patient values.”
The USPSTF’s final recommendations also included three “I” statements, defined as those for which the task force determines “current evidence is insufficient to assess the balance of benefits and harms of the service” because evidence is either “lacking, of poor quality or conflicting.”
The “I” statements relate to screening among women aged 75 years or older; the use of digital breast tomosynthesis as a primary screening method for breast cancer; and the use of breast ultrasonography, digital breast tomosynthesis, MRI or other methods in women found to have dense breasts on an otherwise negative mammogram, a population Bibbins-Domingo said has a small increased risk for breast cancer. – by Anthony SanFilippo
Disclosure: Laine reports no relevant financial disclosures. Please see the full study for a list of all other authors' relevant financial disclosures.
From all of the scientific data examined, it is clear that screening mammography and early detection reduces the risk for death from breast cancer. One of the points that has not been discussed is that early detection also potentially alters treatment that a woman has to undergo for her breast cancer and also may lead to less aggressive treatment. Due to early detection, most women have the option to undergo a lumpectomy instead of a mastectomy. The treatment after surgery also may be altered based on the stage that the cancer was diagnosed.
Over the last several decades, there has been enormous progress in the overall outcome for women with breast cancer. There are many reasons for the fact that 5-year survival for breast cancer is 90%, and early detection is one of them. If — as a result of these recommendations — insurance coverage changes and/or fewer women undergo screening mammograms, we will slowly erode all of the progress that we have made in this arena.
William J. Gradishar
The debate about the utility of mammograms, and the question of when and who should get them, has been discussed endlessly for the last decade.
The U.S. Preventive Services Task Force has issued new guidelines for average-risk women. These guidelines indicate that, between the ages of 40 to 49 years, the decision should be an individual choice that is discussed between patients and physicians. The guidelines recommend women between the ages of 50 and 74 years receive screening every other year.
These recommendations remain controversial. They also are in conflict with other organizations and professional societies (eg, American Cancer Society, National Comprehensive Cancer Network, ASCO and American College of Obstetricians and Gynecologists) that have somewhat different recommendations about when to start screening and the ideal screening interval.
These recommendations do not apply to women with higher risk for developing breast cancer (eg, those with mutations such as BRCA1 or BRCA2).
There is little debate that the impact of mammography for breast cancer detection is greater in older women, whereas the impact is smaller in the younger age group. It is also true that debate and analysis of data remains largely focused on studies that were completed years ago — or, in some cases, decades ago.
Since that time, the technology has changed, but the initiation of new, massive clinical trials to evaluate the impact of mammography in different age groups is unlikely and cost prohibitive.
Well-intentioned experts can come to different conclusions regarding the data available, but the most important message that continues to be a common thread though all the years of debate is that patients should have a discussion with their physician regarding whether they should initiate screening mammography and at what interval.