Cancer rates are rocketing but is it all just ‘bad luck?’
Published 12 Jan 2015
Blog by Lynn Ladbrook, CEO Breast Cancer UK
The New Year has got off to a contentious start as far as news stories on cancer go. For those of us who managed to blunder back into our offices on the 2nd Jan, we were met with the startling (and rather gloomy) news that getting cancer is just “down to bad luck”, followed by the even gloomier news that we must all be getting unluckier as a “record 2.5 million will be living with cancer in the UK in 2015”.
Is getting cancer really just about bad luck? Can we really do nothing to prevent cancer or the doomsday scenario that over half of us are likely to get it at some point in our lives? I for one, along many of us working this field, absolutely refuse to believe that.
The story that getting cancer is just down to bad luck was based on a paper by Tomasetti and Vogelstein, published in Science. They used a statistical model to show that the number of cell divisions that occur in a particular tissue is strongly correlated with the lifetime risk of cancer developing in a particular organ. This is consistent with current knowledge on how cancers originate.
Yet, the research goes on to suggest that random mutations are more significant than environmental and hereditary factors and, therefore, that getting cancer is more about luck or rather ‘bad luck’ than external factors, such as our environment or genes.
This (somewhat sensationalist) assertion didn’t go unquestioned. Bob O’Hara, a biostatistician at the Biodiversity and Climate Research Centre in Germany, responded that these news headlines, and this interpretation of the data, was more about ‘bad journalism’ than ‘bad luck’. He suggests that, whilst interesting, the research simply “explains the relationship between risk of cancer and the number of cell divisions” and the variation between different cancer types – i.e. the more cell divisions there are, the more likely you are to get cancer. He also states that it “said nothing about the proportion of cancers due to cell division.”
The paper that sparked this debate is a complex piece of statistical jiggery pokery. Yet, whatever your interpretation or understanding of what the data does or doesn't say, it's clear that the ‘bad luck’ theory sits uncomfortably with decades of reliable scientific data, which does demonstrate clear correlations between certain tangible risk factors and cancers e.g occupational exposures, geographical clusters, smoking, alcohol and chemicals like DDT and benzene.
It's worth noting that this paper doesn’t analyse breast cancer tissue, nor several other reproductive cancers, due to lack of data. In addition, it doesn’t make any comment about how our environment and lifestyle choices may impact the number of mutations that occur. These, as well as using the rather unscientific term of “luck”, are notable flaws and point to gaps in the paper that undermine the conclusion that getting cancer is just down to bad luck.
For example, we know that oestrogen stimulates cell division of breast cells and that’s partly why breast cancer is so common in the western world, but we are not simply unluckier. We know there are things in our environment, including hormone disrupting chemicals that mimic oestrogen, that potentially increase the chance of mutations occurring and, therefore, increase breast cancer risk. The fact is that breast cancer rates are rocketing and that scientific evidence is increasingly indicating that our exposure to a cocktail of hormone disrupting chemicals could be the root causes of this.
The danger of this ‘bad luck’ theory is that it implies our response should rest entirely on finding a cure. It would be catastrophic if its consequence were to divert attention away from the urgent need for far greater attention to be paid to prevention, an area that is currently overlooked in policy and woefully underfunded.
Advances in knowledge make it clear that we can identify what increases our risk of cancer and, ultimately, that we can beat this terrible disease by investing far more investment into research to prevent it developing in the first place - and that's surely a better outcome than cure. As Thomas Jefferson once said: “...I'm a great believer in luck and I find that the harder I work the more I have it".
2015 will see a host of opportunities for us to influence government policy. We at Breast Cancer UK ask you to help us ensure it’s a year of optimism rather than one of gloom. Together, we can make our voices heard and put prevention where it should be, at the heart of public health policy.
Join us. Pledge to Prevent.