Young women found the news surprising and more than a little scary: Cases of advanced breast cancer have been rising in women 25 to 39 over the past three decades, researchers reported in February 2013.

From 1976 to 2009, the number of cases of advanced breastcancer in younger women at the time of diagnosis increased, the researchers found, from 250 a year to 850 a year.

Although those numbers sound scary, you have to take into account that the population of young women grew in that time period. When you look at the percentage of new cases, the increase is small and shows they nearly doubled: from 1.5 of every 100,000 younger women in 1976 to about 3 per 100,000 in 2009.

WebMD turned to two experts familiar with the study to offer perspective on the findings and suggestions on what younger women should do to protect their breast health. Len Lichtenfeld, MD, is deputy chief medical officer at the American Cancer Society. Laura Kruper, MD, is director of the Cooper Finkel Women's Health Center and co-director of the Breast Cancer Program at City of Hope Comprehensive Cancer Center in Duarte, Calif.

Q: Can you put this new finding in perspective for younger women?

"Younger women should not become overly alarmed at the headline about the increased risk of advanced breast cancer in young women," Lichtenfeld says.

That's not to dismiss the seriousness of such a cancer diagnosis, he says. "It's a serious problem and it's especially difficult for young women and their families to go through."

However, he says, breast cancer in women age 40 and younger is not common. About 7% of all breast cancers occur in women before age 40.

For most younger women who are considered at average risk for breast cancer, the new study should serve primarily as a reminder to become more aware of their breast health, Lichtenfeld says.

A woman is considered at average risk if she does not have a strong family history of breast cancer or have genetic mutations (such as BRCA1 and BRCA2) that raise risk, he says.

While the research was well done, the increase in breast cancer in young women needs to be studied further, says Kruper: "The big question is why?"

That's not known from the study. Experts speculate it could be related to lifestyle changes, such as delayed childbearing, among other possibilities.

The study researchers speculate that improvement in imaging methods or increasing use of imaging may have meant patients were put in a higher ''stage'' group at diagnosis, resulting in more women being classified as having advanced cancer. While they found no direct evidence of that in the study, they say it could still be possible.

"We need to find out if it is a true phenomenon," Kruper says. Next, researchers could focus on why the increase is happening.

Q: Do the study findings suggest younger women not at high risk of breast cancer should begin to get routine mammograms or other imaging tests?

Absolutely not, Lichtenfeld and Kruper agree.

Q: What about breast self-exams?

"The American Cancer Society does not recommend routine breast self-exams," Lichtenfeld says.

Years ago, many organizations promoted breast self-exams, he says, distributing brochures and water-proof reminder cards to hang in the shower. "Then research showed that organized breast self-exam programs really did not lead to a reduction in the severity of breast cancer," he says.

Now, the American Cancer Society says that breast self-exams are ''an option for women starting in their 20s."

In the study, the researchers did not have any information on how the breast cancer was found initially or whether the women did breast self-exams.

Breast exams by a health care professional are recommended every three years for women in their 20s and 30s, and annually for those 40 and older, the society says.

Women should develop breast awareness, Lichtenfeld says. "They should know how their breasts normally feel, so when they shower or dress and feel something different than what they felt before, they should know they need to get that attended to," he says.

More often than not, he says, the changes are normal and noncancerous, but that should not be assumed by a woman or her doctor.

Q: Are symptoms of breast cancer in younger women the same as in older?

Yes, Lichtenfeld says. These may include a mass in the breast, unexplained pain, a change in the texture of the skin, redness, or inflammation.

Any changes in the nipple should be looked at, too, says Kruper, as well as an enlargement in one breast only.

Q: What should a woman do if she notices any of these symptoms?

"Go see your doctor and expect the symptoms to be taken seriously," Kruper says.

Q: What can women under 40 do to lessen breast cancer risk?

"Maintain a healthy body weight and exercise regularly," Lichtenfeld says. "Follow a healthy diet, preferably more plant-based than meat-based."

He gives the advice to keep a healthy body weight, he says, despite a lack of evidence of a link between obesity in childhood or young adulthood and breast cancer. "On the other hand, in postmenopausal women, obesity is a risk factor increasing the risk of breast cancer," he says.

Exercise should be consistent, Kruper says. She tells her patients to get in 40 minutes, four to five times a week. It should be a good cardiovascular workout, she says -- ''not just Pilates or yoga."

Be aware of how much alcohol you drink, Lichtenfeld and Kruper agree. Alcohol raises breast cancer risk, experts agree, but much is not known about the link. Even small amounts of alcohol have been linked with a higher risk, Lichtenfeld says. The American Cancer Society recommends no more than one drink a day, he says.

"According to the research, the less you drink the better," Lichtenfeld says.

SOURCES: Len Lichtenfeld, MD, deputy chief medical officer, American Cancer Society.Laura Kruper, MD, director, Cooper Finkel Women's Health Center and co-director, Breast Cancer Program, City of Hope Comprehensive Cancer Center, Duarte, Calif.Johnson, R. Journal of the American Medical Association, published online Feb. 27, 2013.American Cancer Society: "American Cancer Society Guidelines for the Early Detection of Cancer."

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