The 25-year follow up study, involving almost 90,000 Canadian women, compared breast cancer incidence and mortality up to 25 years in women aged 40-59 who did or did not undergo mammography screening.
The results were reported as follows:
- During the five year screening period, 666 invasive breast cancers were diagnosed in the mammography arm (n=44 925 participants) and 524 in the controls (n=44 910)
- Of these, 180 women in the mammography arm and 171 women in the control arm died of breast cancer during the 25 year follow-up period
- The overall hazard ratio for death from breast cancer diagnosed during the screening period associated with mammography was 1.05(95% confidence interval 0.85 to 1.30), i.e. there was a 5% increased risk of death in the mammography arm
- During the entire study period, 3250 women in the mammography arm and 3133 in the control arm had a diagnosis of breast cancer, and 500 and 505, respectively, died of breast cancer, revealing a similar cumulative mortality from breast cancer between groups.
- After 15 years of follow-up a residual excess of 106 cancers was observed in the mammography arm, attributable to over-diagnosis.
The study concluded:
“Annual mammography in women aged 40-59 does not reduce mortality from breast cancer beyond that of physical examination or usual care when adjuvant therapy for breast cancer is freely available. Overall, 22%(106/484) of screen detected invasive breast cancers were over-diagnosed, representing one over-diagnosed breast cancer for every 424 women who received mammography screening in the trial.”
As we have reported on extensively in the past, x-ray mammography is far more dangerous than the general public is being let on to. For starters, we have spent considerable time indexing research from the National Library of Medicine on the unintended adverse effects of this diagnostic intervention, including evidence for its lack of effectiveness, which can be viewed here: X-Ray Mammography Harms. We encourage our readers to familiarize themselves with the primary literature on these topics, instead of relying exclusively on mainstream news reporting, or simply the authority of ‘experts’ whose interpretations and recommendations are usually policy-driven and not evidence-based.
There are a wide range of problems with conventional breast screenings that we believe everyone should be made aware of, especially considering it is a medico-ethical obligation as a necessary part of informed consent:
- They Contribute to Radiation-Induced Breast Cancer: In our previous article, “How X-Ray Mammograpy Is Accelerating The Epidemic of Cancer,” we addressed the radiobiological hazards of mammography radiation, which is far more carcinogenic than previously believed. Essentially, the radiation risk model used to determine whether the benefit of breast screenings in asymptomatic women outweighs their harm, underestimates the risk of mammography-induced breast and related cancers by between 4-600%. [Note: even the “therapeutic” use of radiation (radiotherapy) to treat breast cancer has been shown to make the cancer cells up to 30x more malignant: “Study: Radation Therapy Makes Cancers 30x More Malignant“]
- They Lead To An Epidemic of Misdiagnosed/Overdiagnosed Breast Cancer: In our previous article, “Mammograms Linked To An Epidemic of Misdiagnosed Cancers,” we addressed the mythology associated with one of the most commonly diagnosed screen-detected breast cancers, namely, Ductal Carcinoma In Situ (DCIS), which has recently been confirmed to be benign in nature (i.e. not ‘cancer’) by a National Cancer Institute commissioned expert panel. For more details, read: “Millions Wrongly Treated for ‘Cancer,’ National Cancer Institute Panel Confirms.” Also, in “Confirmed: The More Mammograms You Get The More Harm They Do,” we reported on a 2012 Journal of the National Cancer Institute study that found annual breast screening for women 40 or older provides no additional protection against aggressive breast cancer, but does cause greater harm through increasing rates of false positives and unnecessary biopsies. Additionally, in “Confirmed: Breast Screenings Cause More Harm Than Good,” we report on a BMJ article that concluded the”[I]ntroduction of breast cancer screening might have caused net harm for up to 10 years after the start of screening.”
- They Cause Psychological Trauma: Beyond the obvious fact that a multi-billion dollar “pink” cause marketing agenda has converted women’s breasts into being perceiving first and foremost as ‘cancer time-bombs,’ the omnipresent psychological threat of being diagnosed with breast cancer, along with the statistical inevitability – at least 1 in 2 women undergoing regular screening will have a false-positive recall or biopsy recommendation after 12 years[i] – of being ‘overdiagnosed,’ i.e. misdiagnosed and [mis-]treated for cancers that weren’t there, or were intrinsically benign/indolent, there is the reality that millions of women will suffer harm from screening that will never be accounted for in studies like the one featured in the beginning of this article. In a previous exploration on the topic, “‘Hidden Dangers’ of Mammograms Every Woman Should Know About,” we reported on a 2013 study from the Annals of Family Medicine, which found that women with false-positive diagnoses of breast cancer, even three years after being declared free of cancer, “consistently reported greater negative psychosocial consequences compared with women who had normal findings in all 12 psychosocial outcomes.” What is even more concerning is that “[S]ix months after final diagnosis, women with false-positive findings reported changes in existential values and inner calmness as great as those reported by women with a diagnosis of breast cancer.” Overdiagnosis can no longer be written off as ‘collateral,’ or ‘the cost of doing business.’ These ‘psychological’ traumas have real physiological consequences, and can directly lead to increased mortality, both through adrenaline’s role in activating malignancy associated genetic pathways within cancer, as well as the recent discovery that the clinical ritual of cancer diagnosis itself can accelerate heart-related deaths up to 26.9 fold within 1 week post-diagnosis. Read: “Research: Some Cancer Diagnoses Kill Quicker Than The Cancer.”
- They Aren’t Evidence-Based/Scientific: On the most fundamental level, exposing the presumably healthy breasts of asymptomatic populations to breast cancer-causing radiation (the equivalent of 300 chest x-rays each screen), makes little sense. This is all the more true now that we know most of the early stage “breast cancers” that have been diagnosed in the quarter century old push for ‘early detection’ via x-ray mammography screenings, were benign lesions, some of which (including so-called “invasive breast tumors”) have been reported to spontaneously regress when left untreated. Given the accumulating evidence against x-ray based screening, and the availability of non-ionizing radiation-based methods such as thermography, why take the well-documented risks? For further research, read our contributor Rolf Hefti’s excellent mini-review: “Why Mammography Is Unscientific and Harmful.”
For additional research on issues related breast cancer, use our health guide: breast cancer.
[i] Rebecca A Hubbard, Karla Kerlikowske, Chris I Flowers, Bonnie C Yankaskas, Weiwei Zhu, Diana L Miglioretti. Cumulative probability of false-positive recall or biopsy recommendation after 10 years of screening mammography: a cohort study. Ann Intern Med. 2011 Oct 18 ;155(8):481-92. PMID: 22007042