Key findings on early screenings for breast cancer

1.4 million new breast cancer cases diagnosed each year.

50,000 to 70,000 cases don't need treatment, the study said.

234 cases of early-stage cancer per 100,000 women are detected because of mammograms -- more than double the number that would otherwise be detected.

8 percent drop in late-stage cancers, from 102 to 94 cases per 100,000 women.

• A government-appointed task force calls for mammograms every other year starting at age 50 and stopping at 75.

• The American Cancer Society recommends them every year starting at age 40.