June 28th, 2012 by Hasham
New Breast Cancer Screening Guidelines Released
New breast cancer screening guidelines for women at average risk of breast cancer, published in CMAJ(Canadian Medical Association Journal), recommend no routine mammography screening for women aged 40–49 and extend the screening interval from every 2 years, which is current clinical practice, to every 2 to 3 years for women aged 50–74. The guidelines also recommend against routine clinical breast exam and breast self-examination in asymptomatic women.
The guidelines, aimed at physicians and policy-makers, provide recommendations for mammography, magnetic resonance imaging (MRI), breast self-exams and clinical breast exams by clinicians. They target average-risk women in three age groups (40–49, 50–69 and 70–74 years) who have not had breast cancer and do not have a family history of breast cancer in a mother, sister or daughter.
“As the Guideline on Breast Cancer Screening was last updated in 2001 and breast cancer screening has since become a subject for discussion amongst doctors and patients, the revitalized Canadian Task Force selected breast cancer screening as the topic for its first guideline,” said Dr. Marcello Tonelli, Chair of the Task Force on Preventive Health Care and Associate Professor at the University of Alberta, Department of Medicine, in Edmonton, Alberta. “We intend that this Guideline, which reflects the latest scientific evidence in breast cancer screening, be used to guide physicians and their patients regarding the optimum use of mammograms and breast examination.”
According to the guideline, outcomes of breast cancer screening such as tumour detection and mortality must be put into context of the harms and costs of false–positive tests, overdiagnosis and overtreatment. False–positive results can have a significant impact on the emotional well-being of patients and families. They can cause lifestyle disruptions and result in costs to both patients and the health care system.
“Providing Canadians with guidelines that reflect the most current scientific evidence is our priority,” said Dr. Tonelli. “We encourage every woman to discuss the risks and benefits of screening with their doctor before deciding on the best approach for them.”
No routine mammography for women aged 40-49 because the risk of cancer is low in this group while the risk of false–positive results and overdiagnosis and overtreatment is higher
Routine screening with mammography every two to three years for women aged 50-69
Routine screening with mammography every two to three years for women aged 70-74
No screening of average-risk women using MRI
No routine clinical breast exams or breast self-exam to screen for breast cancer.
“There was no evidence that screening with mammography reduces the risk of all-cause mortality,” state the authors. “Although screening might permit surgery for breast cancer at an earlier stage than diagnosis of clinically evident cancer (thus permitting the use of less invasive procedures for some women), available trial data suggest that the overall risk of mastectomy is significantly increased among recipients of screening compared with women who have not undergone screening.”
In addition to the full guidelines, one-page information pieces are available for both physicians and patients on the task force website: www.canadiantaskforce.ca
The Canadian Task Force on Preventive Health Care is an independent body of 14 primary care and prevention experts. The task force has been established by the Public Health Agency of Canada to develop clinical practice guidelines that support primary care providers in delivering preventive health care.
In a related commentary, Dr. Peter Gøtzsche, Nordic Cochrane Centre, Copenhagen, Denmark, writes, “these guidelines are more balanced and more in accordance with the evidence than any previous recommendations.”
He states that evidence does not support mammography screening and argues that screening is ineffective and even harmful because diagnosis of cancers that would otherwise be undetected lead to life-shortening treatments and mastectomies.
“The main effect of screening is to produce patients with breast cancer from among healthy women who would have remained free of breast disease for the rest of their lives had they not undergone screening,” writes Dr. Gøtzsche.
“The best method we have to reduce the risk of breast cancer is to stop the screening program,” he concludes. “This could reduce the risk by one-third in the screened age group, as the level of overdiagnosis in countries with organized screening programs is about 50%.”
Breast cancer screening guidelines spark uproar
The mammogram wars have come to Canada.
The new breast cancer screening guidelines, aimed at reducing the potential harms of overscreening, triggered heated debates in the scientific community and sparked outrage in some women and advocacy groups who staunchly believe routine mammography saves lives.
The controversy mirrors the battle that erupted in the United States in 2009 after a government-appointed task force released its recommendations to scale back the frequency of mammography screening for women.
A similar fight is also brewing in the U.K., where the government’s cancer chief launched an independent inquiry in October to quell debate over whether the benefits of mammography outweigh the harms.
Here in Canada, physicians and breast cancer advocates say the new guidelines — meant to bring clarity to a clouded issue — will likely leave many women confused.
“There is still a high level of uncertainty with many of these issues,” said Dr. Eitan Amir, a medical oncologist at Princess Margaret Hospital and Mount Sinai Hospital.
“Women should speak with their family physician to find out what is the best thing for them.”
The guidelines — the first update in a decade — recommend most women avoid routine mammography until age 50, after which they should have the procedure every two to three years instead of every year or every two years.
They also recommend against routinely screening women in their 40s; in 2001 the group offered no advice for women in this age group. And they warn women not to check their breasts for cancer on a regular basis or have their family physician do a clinical exam because there is no evidence either reduces mortality rates.
New breast cancer screening guidelines inflame debate, add to confusion
The scientific panel tasked with sorting out the conflicting signals on breast-cancer screening has only inflamed the debate and left women – and their doctors – even more confused.
New guidelines, written by the Canadian Task Force on Preventive Health Care, are designed to clarify best practices for screening at a time when many experts and advocacy groups remain sharply divided, particularly about the benefits of routine mammograms for women in their 40s.
The long-time approach to screen early and often has now met a new wave of research and recommendations that concludes that routine mammograms for women in their 40s are of negligible benefit and can lead to needless procedures.
The controversy – playing out against the backdrop of a strapped health-care system that has to make hard decisions about resources and costs – has been stirred by the new national screening recommendations, which say Canadian women under age 50 who are at an average risk of developing breast cancer should not have routine mammograms, and that also advises against self-exams at any age.
In addition to limiting mammograms to women age 50 to 74, the guidelines also say clinical breast exams and self-exams have no benefit and shouldn’t be used; that women aged 50 to 69 should have mammograms every two to three years, instead of every year or two; that women aged 70 to 74 should have mammograms every two to three years – previous guidelines didn’t recommend screening for that age group.
The recommendations don’t apply to women with an elevated risk of breast cancer, such as those with a history of the disease in a first-degree relative or those with mutations in the BRCA1 and BRCA2 genes.
But instead of quelling debate, the recommendations are opening a new chapter in the simmering battle.
While many oncologists and groups such as the Canadian Cancer Society say the new recommendations, published Monday in the Canadian Medical Association Journal, are a balanced approach that will focus breast cancer screening programs on women who can benefit most, others believe the move to limit mammograms to those age 50 and over will put lives in danger.
“We’re really disappointed to see these recommendations,” said Sandra Palmaro, CEO of the Canadian Breast Cancer Foundation, Ontario region. “They’re ultimately going to result in more women dying from breast cancer that don’t need to be dying from breast cancer, there’s no question.”
Provinces are responsible for breast cancer screening programs. Many, such as British Columbia, Alberta and Nova Scotia, regularly give mammograms to women aged 40 to 49, while some others, including Ontario and Newfoundland and Labrador, do not. It remains to be seen whether provinces choose to adopt the new guidelines.
At the heart of the debate is an argument about the merits of cancer screening programs. Proponents of mammograms for women in their 40s say they can save lives by detecting cancer early.
But more recently, the tide has been shifting away from the notion that more screening is better. For instance, a U.S. panel ruled in 2009 that women in their 40s should not be screened for breast cancer. The backlash from advocacy groups and experts was so fierce that the rules haven’t been adopted.
Last weekend, the screening controversy showed up in the medical journal The Lancet, which published a letter signed by more than 40 physicians and radiologists, including three Canadians, who detect an “active anti-cancer screening campaign” among a particular group of scientists. The campaign, they say, is marked by “erroneous interpretation of data from cancer registries and peer-reviewed articles.”
Still, more experts in Canada have begun questioning whether support for screening programs has been too zealous, responding to growing scientific evidence suggesting that mammograms for women aged 40 to 49 may not save many lives, but can lead countless women to have unnecessary follow-up treatments and biopsies.
Canadian breast cancer screening guidelines would cost thousands of lives
The American College of Radiology today denounced new breast cancer screening guidelines by the Canadian Task Force on Preventive Health (CTFOPH), which recommend against annual screening of women ages 40-49 and would extend time between screens for older women.
An ACR news release said “the CTFOPH guidelines ignore results of recent landmark randomized control trials which show that regular screening reduces breast cancer deaths in these women by approximately a third” and that “While implementation of the CTFOPH guidelines may save money on screening costs, the result will be thousands of unnecessary breast cancer deaths.”
The ACR stated that the CTFOPH guidelines largely mirror those released by the United States Preventative Services Task Force (USPSTF) in 2009 and that “The USPSTF approach misses 75 percent of cancers in women 40-49 and up to a third of cancers in women 50-74.”
The College pointed to an analysis (Hendrick and Helvie) published in the American Journal of Roentgenology, showed that, if USPSTF recommendations were followed, 6,500 additional women each year in the U.S. would die from breast cancer. The ACR said “A similar proportion of Canadian women will likely die unnecessarily each year from breast cancer if the CTFOPH guidelines are followed.”
Barbara Monsees, MD, chair of the American College of Radiology Breast Imaging Commission, added that “Panels without profound expertise in breast cancer screening should not be issuing guidelines. These recommendations are derived from flawed analyses and they defy common sense. Women and providers who are looking for guidance are getting bad advice from both the U.S. and Canadian Task Forces.”