Two weeks ago, in response to mounting international concern for the welfare of older women, the UK government announced that it is setting up an independent review of the risks and benefits of xray mammography screening.
It has been publicised since the 1970s that low-dose mammographic irradiation may increase risk of breast cancer 4 (to 6) fold, and more so in women with a genetic risk. (Heyes ea 2006 Dept Medical Physics Birmingham Hospital UK; publicised studies -including from survivors of atomic bomb exposure).
A new French study published this month confirms in human breast cancer cells that a significant dose-effect of lowdose irradiation was observed, “with an exacerbation in high-risk compared to low-risk patients (p = 0.01). The dose repetition (2 + 2 mGy) provided more induced and more unrepaired DSB than 2 mGy and 4 mGy, and was exacerbated in HR (p = 0.006). ”
Just three weeks after the last review in this column of the mounting evidence against xray breast screening, at least 4 more major studies (three from USA) have been published the past month refuting the marketing spiel that “Xray screening Mammography Saves Lives” :
1. A trenchant debunking appeared in the New York Times a fortnight ago based on the latest USA Dartmouth University study of USA 20 year national Breast cancer statistics published in a leadng medical journal that day It concluded: “Most (87% to 97% of) women found to have breast cancer by xray screening are not helped by the test. Only some 4% to 8% of women with breast cancer so detected are helped by such screening. Most are instead either diagnosed early (with no effect on their mortality) or overdiagnosed. Thus of millions of average-risk asymptomatic women having breast irradiation screening each year, only 1 in 10 000 really benefit.” They put the risk of having breast cancer found on xray screening at 2% over 10years ie 0.2% per year in a 50year old women, and her 20 year risk of dying of breast cancer at 1% . Most women with screen-detected breast cancer have not had their life saved by screening.
Dr Susan Love a leading USA professor of surgery would like to see “less emphasis on screening and more focus on cancer prevention and treatment for the most aggressive cancers, particularly those that affect younger women. Roughly 15 percent to 20 percent of breast cancers are deadly. And even with screening, bad cancers are still bad. ”
Dr Cornelia Baines an emeritus professor at the University Toronto affirms that “the benefit (of breast xray screening) is much smaller in terms of avoiding death than is the harm arising from over-diagnosis and unnecessary treatment for breast cancer, to say nothing of increased rate of mastectomy associated with screening.These issues are not widely known to the general public. ”
2. Similarly, a massive study from Georgetown University Washington DC, concluded that “Biennial screening from 50-74 reduces the probability of breast cancer death from 3% to 2.3%. Screening annually from 40 to 84 only lowers mortality an additional one-half of one percent to 1.8% but requires substantially more mammograms and yields more false-positives and over-diagnosed cases. Decisions about screening strategy depend on preferences for benefits vs. potential harms and resource considerations”.
3. A pan-USA consortium found that in 170 000 USA women followed with xray screening annually for 10 years, more than half of women received at least 1 false-positive recall, and 7% to 9% a false-positive biopsy recommendation.
And finally a survey of the Swedish screening mammography program since 1986 found similar outcome as in the Norwegian program: “the 4-year cumulative incidence of invasive breast cancer was -significantly higher in the screened group by 49% (982 per 100 000) than it was in the control group (658 per 100 000). Because the cumulative incidence among controls did not reach that of the screened group, we believe that many invasive breast cancers detected by repeated xray screening do not persist to be detected by screening at the end of 6 years, suggesting that the natural course of many of the screen-detected invasive breast cancers is to spontaneously regress”.
It is obvious to most when the light is switched off; and that lengthy exposure to intense sunshine damages- no randomized cotrolled trials are needed. Conversely it took millennia before most educated people recognized that neither our Earth nor Sun are the centre of the universe- and many people still do not believe in human rights..
In contrast to eternal human need for mysticism /spiritualism promoting blind faith in deities and prayer and an afterlife, rationalists like Steven Jay Gould argue irrefutably that science and religion are incompatible non-overlapping magisteria. Even Kierkegaard had to admit this in conceding that its tough going against mainstream belief however strong and wrong the mainstream may be, even though religious belief is simply that- irrational blind faith. From the heart, not from rational reasoning.
Search of Pubmed for “randomized controlled trials screening xray mammography” yields not a single trial. In fact the only truly randomized long trial ever conducted with modern xray mammography – the Canadian Breast Screening trial between 1980 and 1990 and comparing manual self-examination alone versus combined with xray mammography (Miller & Baines 1997) – showed that adding screening xray mammography had no impact on the rate of death from breast cancer at up to 13 years’ follow-up from entry.
This outcome has never been disproven except in the minds of those who zealously promote the $8billion a year xray mammography industry, whatever their vested interests from fundraising organizations to service providers and screening machine manufacturing countries.
There are thus at least 20 studies already published showing that screening xray mammography has no benefits compared to its many risks, for reduction in future breast cancer and breast procedures or mortality.
So it is ethically, morally and scientifically negligent to continue to promote fearmongering xray screening mammography without explaining to women that xray screening has no benefit for survival from breast cancer, and may in fact not just promote fruitles pain, anxiety, mastectomy and radiochemotherapy but also hasten death.
Should screening xray mammography even still be offered as a diease-mongering choice for women ? when it is now so well proven by independent studies and expert reviewers that it offers no benefit over regular manual breast examination, but indeed offers many cumulative risks to women, at great cost to individual women and society.
The analogy is the sale of tobacco smoking and alcohol. Unlike the safe use of moderate social alcohol in private, should aggressive promotion, marketing of xray breast mammography, smoking, alcohol and other addictive drug (like designer antidepressants and other psychotropics) consumption be allowed at all?