Mammograms can be dangerous and do not save lives

In a long-running Canadian study of 90,000 women, the researchers found that, over the course of 25 years, death rates from cancer were about the same for women who had regular mammograms, as they were for those who did not (Published BMJ Feb 2014). There was simply no benefit overall for screening mammograms. 

Canceractive has an extensive article on the risks and benefits, but has consisently taken the view that the risks outweigh the benefits. See Screening mammograms do more harm than good.