Mammographic parenchymal patterns. Risk indicator for breast cancer?

Mammographic parenchymal patterns, originally presented as a new risk factor for breast cancer, have been prospectively studied in a large (27,157 examinations) consecutive screening population. Although there is a significantly higher risk of breast cancer in the so-called dysplastic breasts (P2 and DY pattern groups), the classification is of little practical value, as more than 72% of the cancers in the prevalent population were found in the so-called low-risk breasts (N1 and P1 pattern groups). A similar trend occurred at repeated screening of younger women, in which most of the "incident" cancers were found in the "low-risk" breasts. These patterns should not be used to influence patient management or screening programs.