Weighing the evidence

The 2009 mammogram guidance from the task force was based on the panel's assessment of new research that showed most women over 40 face a 3 percent risk of dying from breast cancer if they have not been screened. Beginning mammogram screening at age 50 and following up every other year reduced that risk to 2.3 percent, compared with 2.2 percent risk starting at age 40.
An extra decade of screening could invite harms such as unnecessary biopsies and tests, the possible treatment of non-deadly cancers and radiation. Women in their forties are also more likely to receive false positive results. Cheap Ugg Boots
Another view of the data showed that starting screening at age 40 led to 5,000 more mammograms, 500 false positive results and 33 biopsies for every breast cancer death prevented, according to LeFevre.