Breasts, define the difference between the sexes, perhaps more than any other element of appearance and they are an emotive indicator of feminism, much admired by men and cherished by women, whose fear of breast cancer and the loss of that essential feminism, seems to be a real and present danger. But, that is largely a myth. Incidence is in fact between 1 and 2 per 1000 per year, dependent upon whether you are pre, or post menopausal. In fact 80% of detected breast cancer occurs in women over the age of 50, so this cohort is the most at risk. However, if we compute that into a ten year risk analysis, then 994 women out of 1000 will not get breast cancer.
Fiona Godlee in the BMJ of March 2006 questioned the ethics of screening and came to the conclusion that it was overstated for efficacy and 'over diagnosis' was a considerable failing of the system. This is reflected in the views of Professor Michael Baum in this critique he wrote in 2008, shortly after he resigned from the programme which he had helped to set up. Principal amongst his thoughts, are that screening does not cure anything it just detects asymptomatic disease; breast cancer, well maybe. But 'catching it early' does not devolve any cure, merely a postponement of the inevitable fate of us all, for a somewhat flawed paradigm of periodic testing, that in itself has unpleasant and somewhat dangerous implications for the recipient, with no gaurantee of longer or better life than would have been the case without it.
Mammography is the current test protocol for the early detection of abnormalities, which involves quite high levels of ionising radation, being delivered in several doses, to ensure an 'allegedly' complete picture of the breast. In fact the dose is equal to 1000x that from a standard chest X-ray, so there is some considerable dangers attached to screening in this manner. This holds true when pre-menopausal women are screened, as is the current plan (coming soon to screening centre near you), because the cumulative dose will increase significantly due to the longer screening periods. A dose level of 1 rad in total is often the case, so over time this can add up to a significant risk for cancer in it's own right. In fact the estimated risk of cancer from mammography was calculated, based upon a life total of 24 screenings, of the digital type (which uses a much lower dose than film screening, usually employed in the UK) that 8.6 women per 10,000 would develope cancer as a result of screening, in itself. That, I would add is not far short of the overall risk of 1/1000 of getting cancer anyway.
The Nordic Cochrane Centre has conducted extensive research on the subject and came to the following conclusions;-
Absolute risk reduction for screening is 0.05%
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Screening led to an absolute risk increase of 0.05% due to a 30% overdiagnosis and overtreatment.
So, for 2000 women screened for 10 years, 1 (that's one) will have her life prolonged and 10 (that's ten) healthy women, will undergo unnecessary treatment including breast removal, chemotherapy and radiotherapy, for no useful purpose. The Centre has produced a leaflet which gives an unbiased and scientific evaluation of screening to enable women to make an informed choice, as opposed to the over emotional and biased view portrayed by the NHS and indeed most Physicians.
There have been many studies undertaken to prove or disprove the efficacy of mammography, and the results have been ambiguous a lot of the time, but the the Canadian Trials are viewed as being amongst the best and it is clearly stated that screening had no impact on mortality (post menopausal women 50-59). Here is the view from the Cancer Prevention Coalition in the US who have considerable reservations about it's outcomes and the forces at work that advocate it's use. And this riposte published in the The Lancet from February of 2002 looked at the attempts to 'rubbish' the Canadian and Malmo trials which, when evaluated showed no difference in mortality between screened and unscreened women (see here for more comment). Even the quite militant screening advocates, the US National Breast Cancer Coalition, indicate that screening only reduces the absolute risk by 0.07% ( in women between 50 and 65).
So at best we can hope for a very small, numerically insignificant reduction or no reduction, in breast cancer in post menopausal women, by mammography screening, for some extremely unpleasant side effects and a 10x higher risk of over diagnosis and treatment. Many cancers detected are in fact benign or self limiting and will regress if left or simply stay the same. We do much harm and very little good by screening and for women with breast cancer, a majority will have found it themselves and screening will have played no part, or worst the lump will have appeared between screenings. In other words screening finds very little vigorous tumours but is good at finding and treating cancers that are not usually life threatening. This skews the picture even more.
And what of cost to the NHS? Well around 2 million tests are undertaken each year and rising. The cost of the tests was £166 million (in 2008) but obviously more now. If we add in the re-tests, biopsy and operation and therapy costs so that we save one women in 2000 (in 10 years) but at the same time treat 10x that number who do not even have cancer, we are talking about £500 million or more. How can the NHS justify this enormous cost without having better outcomes? And why do women tolerate this appalling invasion of their bodies with all the attendant risks, amongst which is the fact that if they have already got cancer at testing, the 'squeezing' effect of the plates is likely to cause it spread much more quickly because of the force employed which is about 200 newtons (45 lbs).
Screening is not prevention, merely the detection of a marker for a given disease, or an actual tumour in the case of cancer. We 'sell' to women the view that we are preventing their untimely demise from cancer by screening, which is of course a complete lie. It is in the interests of all involved in this 'industry' of testing that it continues and proliferates as it has done since 2008, when the 'saintly' Gordon (Brown) decided, without any scientific input, that he would fund a whole new paradigm of test protocols to enable the 'plebs' extend their life spans. As is usual Physicians and the NHS leapt at this opportunity for even more incentive payments to increase their wealth (and power).It reinforced the utilitarian principles that have driven the Neo-Liberal doctrine since Tony Blair's ascendency and for all his heirs and sucessors including the
There are other alternatives for those who are particularly 'at risk' like the genetically disposed cohort, such as MRI and/or thermographic imaging, both of which are significantly more benign, or even entirely so. There is also considerable hope for a simple saliva test that will provide a non invasive test. There is also considerable evidence that maintaining sufficient levels of Vitamin D3 by exposure to sunlight (without sunscreen) can confer protection against breast cancer.
Well ladies, I have strayed into territory that many men would fear to tread, but I feel that you are all being manipulated by the emotional baggage surrounding this issue. Mammography is oversold and is wanting of evidence to justify both it's expense and it's outcomes. It appeals to the emotional attachment you have to a part of your body that feeds your offsprings, tantalises and fascinates most of mankind, and in many ways defines your femininity. It plays to the fears we all have of the 'big C' as John Wayne called it, and gives false hope for a dubious protocol that feeds an industry without morals, and an NHS that kills 25,000 people a year due to preventable adverse events ( Ian Kennedy's report of the Bristol Heart Inquiry). Let us 'clean the stables'of that mess instead of venturing into prevention strategies of little worth.
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