The New Mammography Screening Recommendations

Last October, the US Preventive Services Task Force (USPSTF) issued new recommendations that significantly changed the current guidelines for mammography screening for breast cancer (Ann Intern Med. 2009; 151:716-726). The following are the main points of these recommendations:

• Routine screening for women aged 40 to 49 years is not needed
• Biannual screening for women aged 50 to 74 years
• Current evidence is insufficient to assess benefits/harms of screening women aged ≥75 years
• Against clinicians teaching breast self-examination
• Current evidence is insufficient to assess benefit of MRI (magnetic resonance imaging) or digital mammography.

 These recommendations are based on a systematic review of the evidence regarding screening for breast cancer, which suggests that although women in their 40s and 50s benefit equally from routine screening, those in their 40s experience greater “harms” from screening, primarily in the form of false-positive results, which can lead to unnecessary additional screening, biopsies, and anxiety.

The uproar over the recommendations, especially that women aged less than 50 years need not undergo annual screening, is still being heard, with professional societies and breast cancer groups issuing their own responses (Table). So what should nurses and doctors advise their patients? The answer, although seemingly simple, is not so simple after all.

The American College of Obstetricians and Gynecologists (ACOG) noted that although it welcomes the review of the data, the implications for women and physicians require careful evaluation of the data. ACOG suggested that women and their physicians individually assess the benefits and risks of screening, and that gynecologists continue to counsel women that breast self-examination has the potential to detect cancer.

Breast Cancer Experts in Their Own Words: SABCS
In December 2009, at the major US meeting of breast cancer experts—the 32nd San Antonio Breast Cancer Symposium (SABCS)—a special session was devoted to the new recommendations. Although many experts rejected them, others found them reasonable, including a breast cancer survivor whose experience of a “false-negative” screening is absent from the current debate. The following quotations are taken directly from the SABCS (and 1 online source, used with permission).

A Lot of Patients Are Confused
Edith Perez, MD, Professor of Medicine, Director of the Breast Program, Mayo Clinic, Jack sonville, FL
“The task force report confused a lot of women. The information is not new. The report is based on a reanalysis and reinterpretation of data that have been available for some time. We know that certainly not women who are screened will develop breast cancer, and we are happy about that. But mammography alone and clinical breast exam have been shown to help reduce mortality in those who do have breast cancer. We cannot abandon the one thing we know works as we search for better strategies to identify women with breast cancer. The recommendations at Mayo Clinic and my own recommendations to patients will not change based on the report.”

Delaying Screening in Low-Risk Younger Women
Eric Winer, MD, Director of the Breast Oncology Center and Chief of the Division on Women’s Cancers, Dana- Farber Cancer Center, Boston, MA
“If I were a gynecologist, I would try to make enough time in my day to talk to my patients aged 40 to 50 about this topic. I would emphasize the importance of being aware of changes in one’s breast. I would tell them that indeed there are benefits associated with mammography, but there are also ‘harms,’ as the Task Force called them. I don’t think we can entirely dismiss the psychological and physical consequences of false-positives.

For women at elevated risk, it seems clear that the benefits outweigh the risks. But for women with usual risk, aged 40 to 50, I think a woman needs to weigh the evidence with her physician and come up with a reasonable choice. It is fine if she decides to undergo mammography. But also, based on the data, it is a reasonable choice to wait a few years to begin screening.”

Understanding False-Positives
Carolyn Runowicz, MD, Professor of Obstetrics and Gynecology, Director of the Carole and Ray Neag Compre hensive Cancer Center, University of Connecticut Health Center, Farming ton, CT
“I believe the opposition to the USPSTF recommendations is largely because the Task Force emphasized what they called ‘harms,’ which put their recommendations at odds with those of other professional groups. The timing was also unfortunate, as the implication was healthcare rationing. I believe that women should be informed of the ‘harms,’ but should have them put into perspective. They should also be informed of the benefits of screening mammography.

My advice to women aged 40 to 50 would be to understand there is a possibility of false-positive results, but there is also a reduction in mortality. Lives are saved through screening. For women over age 75, for whom routine screening was also not recommended, I would still advise annual mammography if they are in good health.”

The Role of MRI
Debu Tripathy, MD, Co-Leader, Women's Cancer Program, Keck School of Medicine, University of Southern Califor nia, Los Angeles
“The Task Force recommended we focus on high-risk patients. But the fact is, we don’t know how to identify those at high risk other than by family history or presence of the BRCA gene. Everything else is fussy….In a study presented at SABCS investigators compared mammography and MRI in patients thought to be at high risk for breast cancer. They showed that the 2 modalities found the same number of cancers, but MRI found more ductal carcinoma in situ and stage I cancers, and a lower proportion of stage II and III cancers. Mammography, on the other hand, detected more stage II and III cancers. Clinically, this means that if you detect cancer by MRI, it is likely to be at an earlier stage. This is in high-risk patients only.”

A Huge Step Backwards
Marisa Weiss, MD, President and Founder of Breastcancer.org, Direc tor of Breast Radiation Onco logy and Breast Health Outreach, Lanke nau Hos pital, Ardmore, PA
“The proposed new guidelines are based on research that looks at the effect of breast cancer screening on society from a public health perspective rather than individual women. In proposing the changes, the Task Force members said that starting mammograms later in life and doing mammograms less often would save a large amount of money. It also means that about 3% more women would die from breast cancer each year. The Task Force members felt that the amount of money saved was greater than the value of more lives saved. The 3% decrease in breast cancer survival might seem like an acceptable trade-off when compared with the economic benefits of changing breast cancer screening policies. But the reality is that more women…will die each year from breast cancer, which is neither reasonable nor acceptable.”