The drive to improve five year cancer survival – an NHS priority, or political folly?
In the original Johnny English film, Rowan Atkinson’s hapless spy performs a flawless daredevil penetration into the heart of a hostile occupied building. Dropped by helicopter onto the roof, his use of grappling irons is exemplary, his ability to move through locked doors and windows – textbook. Flushed with his own success, it is only after assaulting several members of staff that he realises he has inadvertently broken into the local hospital instead of his intended target. If you are going to invest a lot of time and effort into something important, no matter how good your intentions might be, it is vital to aim for the right target. When the Government published its NHS Mandate earlier this month, a cornerstone of the proposal was the commendable aim for the NHS to be better at Preventing people from dying prematurely. A key aspect of this is to look at deaths from cancer – so far so good. The details, however, is where there is a problem – the focus is to look at 1 and 5 year mortality rates. It is quite simply the wrong target and will result in bad decisions that will be bad for patients and wasteful of scarce NHS resources. The target should be overall mortality, nothing more and nothing less. 5 year mortality data were originally devised to assess the effectiveness of treatment. Here they are useful – if you want to know how one chemotherapy regime works compared with another then the overall 5 year mortality can be very helpful. The problem comes when we use it to assess overall performance, or start comparing data for different countries. We end up with disturbing headlines such as this from the Daily Mail in 2009. These cause politicians real headaches, and the danger of knee-jerk reactions and bad decisions. The problem with 5 year survival is that they are so easy to manipulate – and the easiest ways to do this bring little benefit to patients, or even harm. The hardest way to really improve survival from cancer is to genuinely improve treatment and care – this is expensive, requires investment in the people who run cancer services, often relies on medical breakthroughs and has no guarantee of success. There are far easier, much more reliable methods for achieving results if you are so inclined, and two may prove irresistible to politicians so dependent on a quick fix and the next set of statistics. Technique 1: Diagnose cancer earlier If you have a cancer that is incurable and you are going to die in three years time despite whatever treatment medicine can offer, then you will fall the wrong side of the 5 year statistic. If, however, I can persuade you to be diagnosed 2 years earlier – through an awareness campaign, or cancer screening for instance, then even if I don’t change your outcome one iota you will have crossed magically into the success side of my statistic – Tada! Of course, for some people an earlier diagnosis may make a difference to their outcome, and we would always want to reduce delays once someone develops symptoms related to cancer, but the evidence is that early diagnosis through screening has a limited impact on overall improvements in survival. Another, more powerful, lure of early diagnosis through screening is the prospect of picking up cancers that are so early that they would not ever become a problem. If these cancers go completely undetected then they will have no impact on the statistics. If, however, they are diagnosed they will, by definition, be treated successfully, and they will add a rosy glow to the 5 year survival data. To take prostate cancer as an example. If you screen for prostate cancer you will save lives – but for every life you save you will need to treat 48 other men who would never have died from their ‘cancer’. Without screening there would be one man who will enter the data, and may or may not survive 5 years. With screening 49 men become statistics – and they are all on the good side. This is a compelling political argument, but is it good for patients? Technique 2: Redefine cancer Cancers like pancreatic cancer are what we all think of when we use the Big C word – nasty, aggressive diseases that are almost impossible to treat and spread rapidly. If the NHS is to be tasked with improving 5 year survival for pancreatic cancer then it is on a hiding to nothing – medicine needs to move on and make a break-through if that is to happen. So to balance the books, as it were, there is a great temptation to put as many easy to treat cancers on the other side of the scales as possible, and the best way to do that is to redefine what we mean by cancer. Terms like Ductal Carcinoma in Situ, which is really a pre-cancerous change in the breast of an uncertain nature, have come under the cancer umbrella in recent years. Treated like any other breast cancer, the survival is phenomenally good and it is fantastic for statistics, but the evidence is that many women are treated for it unnecessarily as it will not always develop into a true cancer. The importance of mortality data The problem with relying on 5 year survival is that it encourages Governments to endorse screening programmes on the basis that they improve statistics, rather than being good for patients. It is vital that all screening programmes are rigorously evaluated for both benefits and harms before they are implemented. If the NHS Mandate looked at overall mortality from cancer instead then the drive to improve would be free from these pressures to artificially manipulate statistics, and the focus could be on better care, as well as public health initiatives that might really make a difference, such as plain packaging for cigarettes. The Government might even be pleasantly surprised. In 2008, the most recent year where full data are available, the World Health Organisation database ranks the UK quite favourably – just above Germany and better than most European countries outside Scandinavia. Maybe a pat on the back is in order for the NHS? Or is that not politically permissible these days? Courtesy of The Binscombe Doctor Blog