Breast Cancer Screening Guidelines Under Debate

Mammogram and breast cancer screening recommendations for middle-aged women debated by experts

(RxWiki News) Although it may seem intuitive that you should get screened early and often for all types of cancers, it isn't always that simple. New breast cancer screening guidelines highlight the role of personal choice in screenings for younger women, but not all experts are in agreement.

New draft recommendations from the US Preventive Services Task Force (USPSTF), a panel of national medical experts, suggested that women between the ages of 40 and 49 make an individual choice about whether to start mammography screening for breast cancer. But other experts are stressing the importance of early screenings.

"Mammography is an important tool in reducing the number of breast cancer deaths," said Michael L. LeFevre, MD, MSPH, a former USPSTF chair, in a press release. "Based on the evidence, the Task Force found that screening is most beneficial for women ages 50 to 74."

In mammography, an X-ray of the breasts is taken to look for signs of breast cancer before symptoms develop. In the recent draft recommendations, the USPSTF suggested that women in the 50- to 74-year-old age group have a mammogram screening every two years.

But other experts have contested some of the USPSTF's claims, including Daniel B. Kopans, MD, professor of radiology at Harvard Medical School, and the American Cancer Society, which recommends that women age 40 and over have a mammogram every year.

"The age of 50 is a manufactured threshold for screening," Dr. Kopans told dailyRx News. "None of the parameters of screening including cancer detection and lives saved change abruptly at the age of 50 or any other age."

For women between the ages of 40 and 49, the USPSTF recommended a more individual approach, taking into account issues like personal values and health history.

“The evidence shows that screening women age 40 to 49 is beneficial as well, but fewer women will avoid a breast cancer death by screening at this age," Dr. LeFevre said. "The number of women who experience a false positive result and unnecessary testing is actually higher."

False positive results can sometimes lead to breast biopsies (where a small sample of the breast is removed for testing) and other follow-up procedures. This might be a source of anxiety and stress to some women, according to the USPSTF.

Beyond false positives, another potential harm of early screening the USPSTF cited was overdiagnosis. Overdiagnosis occurs when a cancer that would have never developed to the point of causing illness is found, diagnosed and treated, possibly with surgery or chemotherapy.

But according to Dr. Kopans, the concerns about false positives and overdiagnosis are misguided and overestimated.

"Mammography does not cause overdiagnosis (pathologists make diagnoses) and it does not cause 'overtreatment' (oncologists determine treatment)," Dr. Kopans said. "Stopping mammography is like removing car engines as the solution to traffic accidents."

According to Dr. Kopans, for every 1,000 women undergoing mammography, about 900 are reassured following the screening and about 100 will require a "recall" or follow-up.

Of these, only about 19 will need a biopsy requiring local anesthesia, and between five and six women will be diagnosed with breast cancer (0.5 percent of the original group), Dr. Kopans said.

“Women deserve to be empowered with the scientific data about the benefits and harms of mammography so they can make informed choices about their health,” said USPSTF Vice Chair Kirsten Bibbins-Domingo, PhD, MD, in a press release. “Supported by the science, every woman should use her own values, preferences, and health history to make the decision that is right for her.”

Women should discuss the potential benefits and harms of breast cancer screening with their doctor.

The USPSTF released its new recommendations April 20. This is a draft that is open for public input and response — not a final recommendation statement. The draft authors disclosed no funding sources or conflicts of interest.

Review Date: 
April 21, 2015