THURSDAY, Jan. 25, 2007 (HealthDay News) -- Mammography rates among women aged 40 and older are declining, an unsettling trend that experts worry could result in more breast cancer deaths down the line.
The new report on the decline follows increases exhibited during the 1990s, and scientists seemed unclear about whether this disturbing direction was temporary or not.
"We're hoping it's just a dip, because we don't want to see the declines," said study author Blythe Ryerson, an epidemiologist with the division of cancer prevention and control at the National Center for Chronic Disease Prevention and Health Promotion, part of the U.S. Centers for Disease Control and Prevention. "But it's a 1.8 percentage point change, which translates into over 1.1 million fewer women sitting within those mammography guidelines during 2000 to 2005, so it's still fairly substantial from our standpoint. It's too early to tell if it is going to continue, but we're certainly going to be watching the numbers."
"Maybe women need to be reminded that, despite mammography being a test that's been around for a long time, it's still the best test," said Dr. Jay Brooks, chairman of hematology/oncology at Ochsner Health System, in Baton Rouge, La. "We have to constantly tell our patients that doing a mammogram is the single greatest screening test to help you detect breast cancer early, and we have very clear evidence that it does reduce mortality."
"We have been noting for some time a gradual decrease in women getting mammograms, and we've been concerned," said Dr. Len Lichtenfeld, deputy chief medical officer of the American Cancer Society. "The bottom line is, fewer women are getting mammograms, fewer breast cancers are detected early. That means more late detection, fewer treatment options and a poorer prognosis for survival."
The U.S. Preventive Services Task Force, an independent panel of experts convened by the Department of Health and Human Services, recommends that, starting in their 40s, women be screened for breast cancer with a mammogram every one to two years.
Several other organizations, including the American Cancer Society and the American Medical Association, recommend breast mammograms for women in this age group, although they don't agree on how often.
Breast cancer is the most commonly diagnosed cancer and the second-leading cause of cancer death among women in the United States. In 2002, at least 182,505 women in the United States received a diagnosis of invasive breast cancer, and 41,514 women died from the disease.
According to background information in the paper, screening mammography can reduce deaths from breast cancer by 20 percent to 35 percent in women aged 50 to 69 and about 20 percent in women aged 40 to 49.
But, since 1999, U.S. women have not met the Healthy People 2010 goal of 70 percent receiving a mammogram in the past two years.
This paper, appearing in the Jan. 26 issue of the Morbidity and Mortality Weekly Report, a publication of the CDC, was based on the Behavioral Risk Factor Surveillance System, which collected information from adult women from 2000 to 2005. Respondents were first asked whether they had ever had a mammogram. If the answer was "yes," they were then asked how long it had been since their last mammogram.
The proportion of women who reported having had a mammogram within the past two years decreased from 76.4 percent in 2000 to 74.6 percent in 2005, a statistically significant difference.
If anything, the numbers could be an overestimate, the paper stated.
The trend could be due to any number of factors, including shortage of personnel at breast imaging centers and financial constraints. "Until we know more about whether this is affecting certain groups of women, it's difficult to know what the barriers are," Ryerson said.
"Are women getting prevention complacency, as with anything we do that is routine?" Lichtenfeld asked. "And do we have enough facilities? There is also an increasing number of uninsured and underinsured. There is no clear simple explanation."
What experts do know is that mammograms are lifesaving.
"Although breast cancer can't be completely prevented, screening mammography can be used to detect breast cancer early, before it's big enough to feel or cause symptoms," Ryerson said. "Really early detection is important, because when the cancer is found and treated at an early stage, the risk of dying from the disease is lower."
"If you're a woman over 40 and have never had one or have, and it's been more than two years, it's essential that you contact your health-care provider and get one scheduled," she said.
To learn more about breast cancer and early detection, visit the American Cancer Society.