What you need to know about breast screening

In 2009, the United States Preventive Services Task Force (USPSTF) created significant controversy and confusion for both providers and patients when they revised their breast screening guidelines. (The USPSTF is promoted as an unbiased group that reviews relevant studies and makes guideline recommendations. Specialists may be asked to review the guidelines but no breast specialists (surgeons or radiologists) were on the actual review panel.)

The guideline development process aims to weigh the potential benefit of services against the potential harm, and make recommendations accordingly. For breast screening, the harms considered were “psychological harms,” imaging tests and biopsies in women who were ultimately found not to have cancer, inconvenience, and the possibility of treating a cancer that might not have been life threatening. Radiation exposure was considered to be a minor concern. Regarding benefits – the only benefit considered was reduction in death rates from breast cancer.

These USPSTF guidelines recommend that women ages 40 – 49 with no history of genetic mutations or chest wall radiation therapy not have routine screening mammograms, but rather discuss the pros and cons with their primary providers. The USPSTF acknowledged that mammography screening reduces death from breast cancer and they recommended screening mammograms every 2 years for women 50 – 74. No recommendation was made for women 75 and older, due to a lack of evidence. They stated that there was insufficient evidence to make a recommendation regarding clinical breast exams.

It is a complicated matter to review studies aimed to assess the risks and benefits of breast screening. Physicians and scientists may reach different conclusions and weigh the evidence differently. In the USPSTF recommendations, even the method used to evaluate potential benefits and harms was controversial. Consequently, various organizations have rejected or embraced the USPSTF guidelines.

A recent study in the journal Radiology assessed benefits of screening other than death. They found that for women 40 – 49, increased screening results in earlier detection of breast cancer allowing for reduced need for chemotherapy, less need for total mastectomy, and lower rates of recurrence. Many studies have demonstrated a 30% reduction in breast cancer deaths, most of which is thought to be related to early detection with mammography. It is also true that 20% of breast cancers are detected in women under 50. And it is likely that the potential harms of screening will be lessened when patients are seen at accredited Centers with experienced breast radiologists and surgeons.

Swedish Cancer Institute physicians continue to endorse the American Cancer Society breast screening guidelines which recommend clinical breast exams about every 3 years ages 20 – 40 and annually thereafter, and yearly screening mammograms starting at age 40 and continuing for as long as the woman is in good health, and that women are familiar with their breast exams. It is also important for women to know their family histories, since other screening may be recommended for women with an increased breast cancer risk.

The important message is that breast screening saves lives, breasts, and reduces the possibility of needing chemotherapy.

For more information, talk to your health care provider.