Just the facts: mammography saves lives with little if any radiation risk to the mature breast.

Mammography screening is one of the major medical advances of the past several decades. Prior to 1990, the death rate from breast cancer had been unchanged in 50 y. Mammography screening began on a national scale in the middle of the 1980s and, as would be expected, the death rate from breast cancer began to drop in 1990. Since 1990, the death rate from breast cancer has decreased by 30%. Studies in the Netherlands and Sweden, using direct measurements in the general population, show that most of the decrease is due to mammography screening beginning at the age of 40 y, with a small component due to improved therapies (therapy is more effective when cancers are small and earlier stage). A major concern raised in the 1970s was that the radiation from mammography might cause more cancers than would be cured. Not only did this prove to be a huge overestimate, but it has become clear that it is radiation delivered to very young women (teenagers and women in their early twenties), before terminal differentiation has taken place, that presents the greatest risk. Once the breast has differentiated, the risk from radiation is markedly reduced. By the time women reach their late thirties and early forties, there is no measurable risk from mammographic doses, and even the extrapolated risk is far below even the smallest benefit from screening. Hundreds of millions of mammograms have been obtained since the 1980s. If mammography were causing cancers, the incidence of breast cancer would be increasing. In fact, it is decreasing. Women need to be provided with this information to be reassured that mammograms save lives and that the radiation risk is minimal.