• Mammography Less Accurate for Detection of Second Cancers

    Among women with a personal history of breast cancer, mammography can detect second cancers at an early stage, but may be less accurate than among women who have never had breast cancer. These results were published in the Journal of the American Medical Association.

    Women who have had breast cancer in the past are at increased risk of developing a second breast cancer. This second cancer may develop in either breast. 

    Breast cancer survivors often undergo regular screening mammography in order to detect second cancers at an early stage. There is limited information, however, about how well mammography performs among women with a history of breast cancer.

    To explore the performance of screening mammography among women with a personal history of breast cancer, researchers collected information about more than 100,000 screening mammograms. These mammograms were performed in roughly 19,000 women with a personal history of early-stage breast cancer and 55,000 women without a personal history of breast cancer.   

    • As expected, the cancer rate per 1000 mammograms was higher among the women with a personal history of breast cancer than among without a personal history of breast cancer (10.5 versus 5.8).  
    • The sensitivity of mammography (the ability of a mammogram to detect a cancer) was lower among women with a personal history of breast cancer. Screening mammography detected 65.4% of the breast cancers in women with a personal history of breast cancer and 76.5% of breast cancers in women without a personal history of breast cancer.
    • The breast cancers that were diagnosed in study subjects were predominantly early-stage. 

    These results suggest that mammography may be less accurate among women with a personal history of breast cancer. Nevertheless, the cancers dectected in women with a personal history of breast cancer were typically detected at an early stage and many still were found on mammography."

    The researchers note “Our findings support annual mammography screening recommendations in PHBC [personal history of breast cancer] women, but also highlight issues needing further evaluation.” It remains uncertain, for example, whether certain subgroups of women with a personal history of breast cancer would benefit from additional or alternative approaches to breast cancer screening.

    Reference: Houssami N, Abraham LA, Miglioretti DL. Accuracy and outcomes of screening mammography in women with a personal history of early-stage breast cancer. JAMA. 305:790-799.