Screening mammography in the elderly: a case-control study.

This case-control study tested the hypothesis that elderly women with metastatic breast cancer were previously screened less than controls. Cases included women over 60 years old who had metastatic breast cancer; the tumor registry provided controls. Identical criteria yielded comparable groups (cases = 109, controls = 211) receiving primary care at this tertiary center. Radiology and medical records were examined for mammograms; these were blindly categorized "diagnostic," "screening," or "indeterminant." The major, unexpected finding was that less than 6% of controls had ever had screening mammography. The associations between screening and metastatic cancer (odds ratios) suggest a beneficial effect of screening: OR/0.73 for ever screened and OR/0.71 if screened within the year of cancer diagnosis. All confidence intervals include one; however, low screening participation leaves this study with little power. The major implication is that despite the current recommendations, the elderly are not being included in screening mammography programs.