Breast Cancers Arising between Mammograms Have Aggressive Features
Breast cancers that are discovered in the period between regular screening mammograms—known as interval cancers—are more likely to have features associated with aggressive behavior and a poor prognosis than cancers found via screening mammograms. These high-risk features include higher stage and grade, larger size, and lack of estrogen receptors (ER) and progesterone receptors (PR), researchers reported online May 3 in the Journal of the National Cancer Institute.
The results highlight the need for more sensitive screening methods and for women to monitor their breast health between mammograms, concluded Dr. Victoria Kirsh of Cancer Care Ontario and her colleagues.
The researchers compared the traits of breast cancers in women who had been screened in the Ontario Breast Screening Program between 1994 and 2002. The analysis included 87 women who had “missed” interval cancers, 288 women who had true interval cancers, and 450 women whose cancers were detected by screening mammography. Missed interval cancers were cancers that could have been detected by mammography but were overlooked due to error or difficulty in reading the x-ray films. True interval cancers were not detectible at the time of last screening, even on review.http://www.cancer.gov/dictionary?CdrID=46409