Cancer research 50 years and counting new report

Cancer  research – 50 years and counting

17/07/15

Christopher P. Wild, Director at the International Agency for Research on Cancer (IARC) outlines how 50 years on, prevention still remains key to cancer research…

“Have you found a cure yet?”

Which cancer researcher upon revealing their profession has not faced this question? One can respond confidently with examples of major improvements in survival: childhood leukaemia, testicular and breast cancers being notable. One can point to remarkable insights into the previously hidden biology of cancer, with drugs now tailored to exploit the molecular Achilles heel of an individual tumour. These triumphs of scientific creativity and endeavour merit the telling. Yet the disturbing, deeper truth is we cannot treat our way out of the cancer problem.

As people live longer and populations increase, the number of new cancers each year is projected to rise sharply. In 2035, just 20 years from now, there will be an estimated 10 million more people every year facing a cancer diagnosis. Increases are greatest in the developing countries where there is least capacity to treat and care for patients. The spread of risk factors linked to western patterns of individual behaviour and societal structure will exacerbate the problem. Even for the world’s richest countries the spiralling cost of cancer means improved treatment alone is an inadequate response. For the world’s poorest, the out-of-pocket expenses of treatment for one individual can be financially catastrophic for an extended family. The pain of cancer is far reaching. How did we end up here and what might be done better?

Fifty years ago, when the International Agency for Research on Cancer (IARC) was established, IARC scientists considered the striking global variations in cancer patterns and decided to study the causes of this heterogeneity as an avenue to prevention. Over the last 5 decades IARC played its part, with many others, in discovering human carcinogens. Tobacco remains the pre-eminent culprit. Chronic infections account for 16% of all cancers, one in 4 in the most populous nation, China. Alcohol, radiation including excess sunlight, unhealthy diets, environmental contaminants and occupational exposures all contribute. Imbalances in calorie intake and expenditure are adding to the problem; many people are no longer moving enough to justify the amount they eat and drink.

Estimates vary but one can safely conjecture that some 40-50% of cancers could be prevented by translating this accumulated knowledge into interventions. Further inroads are made by detection of early-stage cancers or pre-cancerous conditions, combined with more effective treatment e.g. for cervical, breast, colorectal and oral cancers. Furthermore, prevention and early detection demonstrably work. Major declines in lung cancer following reduced tobacco consumption are remarkable as are the falls in cervical cancer following introduction of screening. Improved protection against work place carcinogens form part of the successes. Vaccination against hepatitis B virus and human papilloma viruses will in time yield their fruits. Many interventions have added value through reducing other illnesses of aging such as cardiovascular disease and diabetes.

Despite proof and promise, prevention is too often neglected. Commonly less than 5% of cancer research funding goes to prevention, a proportion dwarfed by the investment in basic science and clinical translational research. In addition, the science that is performed too often remains at the stage of proof-of-principle, with a failure to implement. This under-investment in research and in implementation is costly and while the underlying drivers are complex, they merit exploration.

Part of the problem may be time. The benefits of prevention can take many years to manifest. This is incompatible with the duration of a political mandate (at least in most democracies) but also with the immediacy of people’s personal experience, where what is sought is a cure. Economics is important, because while new therapeutics offer opportunities for private sector investment and growth, public health interventions are perceived as cost pressures. Complexity is a further element. Prevention requires a multi-sectoral cooperation across health, transport, environment, etc., to address the “causes of the causes”. Responsibility has been too often placed solely on the shoulders of the individual whereas tobacco control has shown how appropriate legislation has been key to success.

Nevertheless, this is an exciting time for cancer prevention. Advances in cancer biology offer fresh impetus to studies of causes, early detection and prevention. Implementation research, close to policy, can better indicate factors which help or hinder the translation of promising interventions into effective national programmes. Thorough analyses of the economic benefits of prevention may yet reduce the unpopularity of the Minister of Health among government colleagues. Prevention, applied at the population level, offers a sustainable approach contributing in turn to reduced inequalities in society.

From a global perspective the necessity of prevention is blindingly obvious. IARC enters its second 50 years with a renewed mandate to conduct cancer research for cancer prevention. As there is an undeniable responsibility to offer the very best in treatments for the patients of today, there is also an undeniable responsibility to prevent the suffering from cancer for the populations of tomorrow. Perhaps eventually, on revealing one’s identity as a cancer researcher to a new generation, the question may just occasionally be: “Can you prevent it yet?