Cancer prevention as part of precision medicine: 'plenty to be done'

Abstract

Cancer burden worldwide is projected to rise from 14 million new cases in 2012 to 24 million in 2035. Although the greatest increases will be in developing countries, where cancer services are already hard pressed, even the richest nations will struggle to meet demands of increasing patient numbers and spiralling treatment costs. No country can treat its way out of the cancer problem. Consequently, cancer control must combine improvements in treatment with greater emphasis on prevention and early detection. Cancer prevention is founded on describing the burden of cancer, identifying the causes and evaluating and implementing preventive interventions. Around 40-50% of cancers could be prevented if current knowledge about risk factors was translated into effective public health strategies. The benefits of prevention are attested to by major successes, for example, in tobacco control, vaccination against oncogenic viruses, reduced exposure to environmental and occupational carcinogens, and screening. Progress is still needed in areas such as weight control and physical activity. Fresh impetus for prevention and early detection will come through interdisciplinary approaches, encompassing knowledge and tools from advances in cancer biology. Examples include mutation profiles giving clues about aetiology and biomarkers for early detection, to stratify individuals for screening or for prognosis. However, cancer prevention requires a broad perspective stretching from the submicroscopic to the macropolitical, recognizing the importance of molecular profiling and multisectoral engagement across urban planning, transport, environment, agriculture, economics, etc., and applying interventions that may just as easily rely on a legislative measure as on a molecule.

Figure 1.

The five most common cancers in 2012 according to levels of the Human Development Index (HDI) across the 184 countries included in GLOBOCAN. HDI is a composite measure of life expectancy, educational attainment, and command over the resources needed for a decent living (UNDP, 2013) and is used in this study to examine the cancer profiles according to four levels of societal development: low HDI (HDI < 0.53); medium HDI (0.53 ≤ HDI < 0.71); high HDI (0.71 ≤ HDI < 0.80) and very high HDI (HDI ≥ 0.80). [United Nations Development Programme (UNDP). Human Development Report 2013. The Rise of the South: Human Progress in a Diverse World (2013). New York: UNDP.]

Figure 2.

Regional variation in the burden of infection-related cancers. H. pylori, HBV and HCV, and HPV are responsible for 1.9 million cancer cases globally, including mainly gastric, liver and cervical cancer respectively. Infection with HIV substantially increases the risk of virus-associated cancers, through immunosuppression.