SAN FRANCISCO --

Less than two years after a key government task force recommended that most women in their 40s may not need mammograms, the nation's largest group representing obstetricians and gynecologists has advised women in that age group to have annual mammograms.

The American College of Obstetricians and Gynecologists on Wednesday issued the new guidelines, which recommend that woman get annual mammograms starting at age 40. Previously, the group recommended mammograms every one to two years starting at age 40, and annually beginning at age 50.

"We know mammography saves lives. If you can find cancer earlier, we know we're doing some good," said Dr. Mary Gemignani, an associate attending physician in breast surgery at Memorial Sloan-Kettering Cancer Center in New York City who helped write the new screening guidelines.

"We know from a cancer perspective that women in their 40s often have more aggressive tumors and by shortening the interval (between screenings), the cancer may be detected earlier," she said.

The new guidelines put the group in line with other organizations, including the American Cancer Society, the American College of Radiology and the Society of Breast Imaging.

But in November 2009, the U.S. Preventive Services Task Force, a government-sponsored group that provides guidance to doctors, insurance companies and policymakers, came out with controversial guidelines that suggested women in their 40s may not need regular mammograms and that women 50 and older should get them every other year instead of annually.

The risks for women

Women have a lifetime risk of about 12 percent of developing breast cancer, but less than 2 percent of women in their 40s develop the disease.

The 2009 recommendations acknowledged that mammograms were found to reduce breast cancer deaths in women aged 40-49 by 15 percent, but determined that wasn't enough to warrant routine mammography at age 40. The risks include radiation exposure and unnecessary biopsies. The group also found insufficient evidence to support screening after age 74.

Dr. George Sawaya, a UCSF professor in obstetrics, gynecology and reproductive sciences who served on the U.S. task force and voted for its new guidelines, said the two recommendations are not as different as they appear.

Sawaya, who is also a member of the American College of Obstetricians and Gynecologists, said the task force did not discourage women in their 40s from having mammograms but, instead, suggested they discuss the potential risks of screenings with their doctors.

"The task force said for women in their 40s and older, it's an individual decision based on their values and the benefits and harms," he said.

Nancy Brinker, founder and chief executive officer of Susan G. Komen for the Cure, lauded the new guidelines issued Wednesday and called the task force's 2009 recommendations "confusing and clumsy."

"The more confused the public is, the less screenings that will occur," Brinker said. "Every time we have one of these debates, more people are confused. These guidelines go a long way at clearing up some of those issues."

Anger over confusion

Another breast cancer advocacy group, Breast Cancer Action in San Francisco, agreed that the dueling guidelines create confusion. The organization supports the task force's 2009 approach, contending scientific evidence does not warrant mammography in younger women at low risk.

"We are incensed about this confusion. Our concern is that putting out new recommendations without any supporting evidence puts women in an impossible situation," said Karuna Jaggar, executive director of the group.

Jaggar said the focus needs to shift to preventing breast cancer in the first place. "Mammography works in some situations, but there are limits and there are risks," she said. "Screening is always going to be a tool. It will never be the answer. We need to get at the root of this problem."