When You Should Get a Mammogram: Weighing the Pros and Cons of Starting Early

— -- When Food Network star Sandra Lee announced she had breast cancer on "Good Morning America" today, she stressed that she got her mammogram two years early.

"I'm 48 years old. I've got -- I've got a couple years 'til 50," she told ABC News' Robin Roberts. "If I would have waited, I probably wouldn't even be sitting here."

Different organizations offer different recommendations when it comes to mammograms, but that can get confusing.

For instance, the U.S. Preventive Services Task Force, which is the national independent panel of experts that makes recommendations on when people should get medical tests, says that women should begin to get mammograms, which are an X-ray of the breast that can detect cancer, every other year starting when they turn 50. But the American Cancer Society, the American Medical Association and the American Congress of Obstetricians and Gynecologists say women should get annual mammograms starting when they're 40.

"There continues to be controversy regarding breast cancer screening: both when to do it, what method to use, and who should be screened," said Dr. Jennifer Ashton, ABC News medical contributor and a practicing OBGYN. "Part of the reason for this confusion is due to the fact that data can and is interpreted by different organizations in slightly different ways."

USPSTF doesn't deny that patients die of breast cancers in their 40s, but it says mammography benefits don't outweigh the harms. The potential harms of mammography include stress, unnecessary additional imaging, unnecessary biopsies and unnecessary treatment for cancers that wouldn't end up killing the patient, said Dr. Donna Plecha, director of breast imaging at U.H. Case Medical Center in Cleveland, Ohio.

"Other people say, 'No that's not a harm to me. You're being thorough,'" Plecha told ABC News. "It really depends on your point of view."

"I think mammography saves lives," she said.

Plecha said of every 1,000 people who undergo a mammogram, on average, 900 will have negative results and 100 will be recalled for additional tests. Of those, 26 will be asked to return in 6 months and 19 will need biopsies. Between five and eight of these patients will be diagnosed with breast cancer, Plecha said.

Ashton said patients should work with their doctors to determine what's best for them.

"Medicine is not 'one-size-fits-all' and this is no different," Ashton said. "Each woman is an individual and her risk needs to be assessed by her health care provider so that the best course of action for her can be determined. There is no such thing as a perfect screening test, but rather today, different approaches for women based on their age, family history and personal risk factors."