Screening mammography in women 40 to 49 years of age: a systematic review for the American College of Physicians.
BACKGROUND
The risks and benefits of mammography screening among women 40 to 49 years of age remain an important issue for clinical practice.


OBJECTIVE
To evaluate the evidence about the risks and benefits of mammography screening for women 40 to 49 years of age.


METHODS
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.


METHODS
Previous systematic reviews; randomized, controlled trials; and observational studies.


METHODS
Two independent reviewers.


RESULTS
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.


CONCLUSIONS
Few randomized, controlled trials assessed the risks of screening, and the literature search was completed in 2005.


CONCLUSIONS
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.
Armstrong
Katrina
K
University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA.
Moye
Elizabeth
E
Williams
Sankey
S
Berlin
Jesse A
JA
Reynolds
Eileen E
EE
D000328:Adult; D000367:Age Factors; D000368:Aged; D001943:Breast Neoplasms / Q000175:diagnosis* / Q000401:mortality / Q000628:therapy; D005188:False Negative Reactions; D005260:Female; D006801:Humans; D008327:Mammography / Q000009:adverse effects / Q000523:psychology; D008403:Mass Screening / Q000009:adverse effects / Q000523:psychology; D008875:Middle Aged; D010146:Pain / Q000209:etiology; D018570:Risk Assessment; D014481:United States / Q000453:epidemiology