A new study questions the value of mammograms for breast cancer screening.  It concludes that a woman is more likely to be diagnosed with a small tumor that is not destined to grow than she is to have a true problem spotted early.

According to WILX-TV 10, mammograms do catch deadly cancers and save lives.  But they also find many early cancers that will never threaten health.

The study tracked tumor sizes before and after mammograms came into wide use, and what effect screening had on death rates.  The study was published Wednesday by the New England Journal of Medicine.