– Breast cancer overdiagnosis remains widespread: Women routinely subjected to unneccesary chemo and radiation (Natural News, March 30, 2015):
Health experts are becoming increasingly concerned about the problem of breast cancer overdiagnosis: Women who, because of mammogram recommendations, are subjected to excruciating surgery, radiation or chemotherapy to treat cancers that never would have become dangerous, and which they never would have known about if not for the mammogram.
An independent panel from the United Kingdom concluded in 2012 that 19 percent of all breast cancer diagnoses are overdiagnosis, detecting cancers that pose no health risk. Other estimates have ranged from 5 percent to as high as 50 percent.
In a recent article in the prestigious British Medical Journal (BMJ), public health expert Alexandra Barratt of the University of Sydney argues that figuring out true rates of breast cancer overdiagnosis needs to be a major public health priority so that women can be given the information to make informed health decisions.
Women need better information
Barratt notes that after early studies suggested that breast cancer screening could reduce death rates by as much as 30 percent, many countries launched publicly funded programs to screen all women past a certain age. Yet while such programs have dramatically increased the number of cancers that are detected, rates of advanced breast cancer have decreased only slightly or not at all. This suggests that the health benefit from widespread mammography is quite slim.
According to the British National Health Service (NHS), 70 percent of women who receive a breast cancer diagnosis receive radiation and hormone therapy, and 99 percent receive surgery.
Potentially high rates of overdiagnosis make it even more important that changes in screening guidelines or new screening technologies such as 3D mammography be carefully evaluated before being adopted. The decision to screen or not should be a personal health decision made based on informed consent, she says, urging governments not to set “participation targets” for screening programs.
So far, efforts to educate the public about screening risks have had limited success. In spite of a 2009 recommendation that mammograms be given to women over the age of 50 every other year, most U.S. women are still following the old recommendation (yearly screening starting at age 40). And although the NHS began issuing information about the risks of overdiagnosis in 2013, a recent study in the British Journal of Cancer found that about 40 percent of women failed to properly understand the material.
Screening benefits overstated
According to a comprehensive review of 50 years worth of research published in JAMA in April 2014, the benefits of mammograms have been overstated and the risks downplayed. The review concluded that for every 10,000 women in their 40s who get a yearly mammogram for 10 years, 190 cases of cancer will be detected. Of these, 25 will be fatal in spite of any treatment, and only 5 will be cured because of early detection. The other 165 are cases that would have been cured even with later detection. Assuming an overdiagnosis rate of about 20 percent, 36 of those 165 cases are cancers that would never have been dangerous.
Additionally, more than 50 percent of the 10,000 women would, in 10 years, receive at least one false positive requiring unnecessary, anxiety-provoking followup tests.
The problems are not unique to breast cancer screening. As noted by United States Preventive Services Task Force Chair Ned Calonge in 2009, “there are five things that can happen as a result of screening tests, and four of them are bad.” In addition to overdiagnosis, bad results include detection of a cancer that will be fatal regardless, falsely detecting cancer where none exists, or failing to detect a dangerous cancer and thus conferring false sense of safety.
In addition, many cancer screening methods – including mammograms – use radiation, and can actually increase lifetime cancer risk.
(Natural News Science)