The limitations of mammography often relate to breast density. Many women with dense breasts are younger although there are women in their 80's with dense breasts. The normal dense glandular tissue can hide a cancer. 3D mammography - tomosynthesis - was approved by the FDA in 2011 and may help mammographers find cancers in women with dense breasts. A landmark study called DMIST also showed that digital mammography helps overcome some of the limitations of mammography. Digital mammography as opposed to analog mammography was shown to find more cancers in young women under 50, women with dense breasts and pre or peri-menopausal women.
Although mammography is not perfect, it has been shown to save lives and screening mammograms are recommended for normal risk women beginning at age 40. If you think you are at higher risk - maybe because of family history, for example - you should ask your doctor about starting screening mammography earlier or adding supplemental imaging exams.