Andrea Mitchell reveals breast cancer, tells women to be screened

(CBS) Andrea Mitchell has breast cancer. The veteran NBC correspondent made that jarring revelation on the air Wednesday, saying the malignancy hadn't spread and that her prognosis was excellent.

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"I had planned to be hiking in Wyoming last week but instead discovered that I am among the one in eight women in the country - incredibly, one in eight - who have had breast cancer," she said during her MSNBC show, "Andrea Mitchell Reports."

Mitchell, 64, said her cancer had been detected during routine screening, and urged women to get screened.

"Screening works," she said. "Do it."

But does it really? The effectiveness of mammography has been called into doubt by recent research. A 2010 study published in the New England Journal of Medicine showed that a nationwide screening program was only marginally effective.

"We conclude that our results supported the evidence that screening mammography reduces the rate of death from breast cancer," the authors concluded. "However, the magnitude of this benefit seems modest."

What does the American Cancer Society say? It says women should have an annual screening mammogram and continue to do so as long as they are in good health. In addition, the society says, women in their twenties and thirties should have doctor examine their breasts at least every three years - and women age 40 or older should have such an exam every year.

The society calls breast self-exams "an option" for women starting in their twenties, saying the exams have been shown to play a small role in finding breast cancer.

Mitchell said she was back at work but gave no details on her treatment. Like many breast cancer patients, she may be in for a long hike - just not the sort of hike she had been planning.

The American Cancer Society has more on breast cancer.