Breast Cancer History Lowers Accuracy of Mammogram
Mammogram's sensitivity lower in the initial five-year period after the first cancer
TUESDAY, Feb. 22 (HealthDay News) -- Mammography screening for breast cancer may be less accurate among women with a personal history of breast cancer (PHBC), despite a higher underlying cancer rate, relative to women without PHBC, according to a study published in the Feb. 23 issue of the Journal of the American Medical Association.
Nehmat Houssami, M.B.B.S., Ph.D., of the University of Sydney in Australia, and colleagues investigated the accuracy of mammography breast cancer screening among women with PHBC. They studied screening mammograms in women with and without a history of early-stage breast cancer and calculated the accuracy of the screening test (based on the scan's final assessment), the cancer detection rate, the interval cancer rate, and the stage at diagnosis.
The researchers found that, despite higher rates of cancer, cancer detection, and interval cancer, the mammogram's sensitivity was significantly lower among PHBC women compared to non-PHBC women (65.4 versus 76.5 percent). Screening sensitivity and detection was higher for in-situ tumors compared to invasive cancer in PHBC women. Among the PHBC women, the mammogram's sensitivity was lower in the initial five-year period after the first cancer, and subsequently increased. Most of the cancers detected in both groups of women were at the early stage.
"Screening mammography detects early-stage breast cancers in PHBC women but has lower accuracy relative to screening women without PHBC. Despite a relatively high interval cancer rate, interval cancers in PHBC women had generally favorable stage distributions," the authors write.