Clinical Health Updates

Guideline: Mammography optional in women 40-49

Clinical Question:
Should screening mammography be used in women between the ages of 40 years and 49 years?

Bottom Line:
Although few women 50 years of age or older have risks from mammography that outweigh the benefits, the evidence suggests that more women 40 to 49 years of age have such risks.

Reference:
Armstrong K, Moye E, Williams S, Berlin JA, Reynolds EE. Screening mammography in women 40 to 49 years of age: a systematic review for the American College of Physicians. Ann Intern Med 2007;146:516-526.

Study Design:
Practice guideline

Synopsis:
The risks and benefits of mammography screening among women 40 to 49 years of age remain an important issue for clinical practice. The authors evaluated the evidence about the risks and benefits of mammography screening for women 40 to 49 years of age. They looked at only english-language publications in MEDLINE (1966-2005), Pre-MEDLINE, and the Cochrane Central Register of Controlled Trials and references of selected studies through May 2005. Selected only previous systematic reviews; randomized, controlled trials; and observational studies. In addition to publications from the original mammography trials, 117 studies were included in the review. Meta-analyses of randomized, controlled trials demonstrate a 7% to 23% reduction in breast cancer mortality rates with screening mammography in women 40 to 49 years of age. Screening mammography is associated with an increased risk for mastectomy but a decreased risk for adjuvant chemotherapy and hormone therapy. The risk for death due to breast cancer from the radiation exposure involved in mammography screening is small and is outweighed by a reduction in breast cancer mortality rates from early detection. Rates of false-positive results are high (20% to 56% after 10 mammograms), but false-positive results have little effect on psychological health or subsequent mammography adherence. Although many women report pain at the time of the mammography, few see pain as a deterrent to future screening. Evidence about the effect of negative screening mammography on psychological well-being or the subsequent clinical presentation of breast cancer is insufficient.