Public Health Solutions Series: Stemming the tide of cancer in Aotearoa New Zealand

This blog looks at solutions to reduce cancer: action on tobacco products; reducing infectious diseases and focusing on system level solutions. 

The blog is part of the Public Health Solutions series looking at effective public health measures to reduce demand on healthcare quickly.

In a recent issue of the medical journal The Lancet, a colleague and I had the opportunity to co-author a commentary on the latest findings from the Global Burden of Disease (GBD) study.  The study had examined the relationship between indicators of metabolic, occupational, environmental and ‘behavioural’ risk factors and cancer.  In their study, the authors estimated that 44% of cancer deaths – and 42% of cancer disability-adjusted life years (DALYs) – could be attributed to these risk factors, and they identified smoking, alcohol and obesity as being the most important among them.   

More than 19 million new cancer cases were diagnosed in 2020 worldwide, and 10 million people died of cancer.  Recent projections indicate that there will be an approximate doubling of people with cancer aged over 65 in the Oceania region by 2035.  And then there is the considerable issue of how these cancers are distributed within the population: in Aotearoa New Zealand, Māori tend to be diagnosed with cancers that have poorer outcomes than non-Māori, such as lung, liver and stomach.  Aside from the incalculable human cost associated with a substantial rise in the number of new cancer patients, such a rise will also exert extra pressure on public cancer services from diagnosis through to treatment, which are already pressed to meet current demand.   

So what can we do in Aotearoa New Zealand to stem the tide of cancer cases?  Below are two things we should do immediately – and one thing that we shouldn’t – to reduce the overall burden of cancer, and also disproportionately reduce the incidence and impact of cancer for Māori. 

1. Firstly, we must continue to limit the availability and accessibility of tobacco and tobacco-adjacent products, including vaping.  Lung cancer is by far the most common cause of cancer death for Māori, killing more Māori each year than the next five or six cancers combined.  We must continue to pass and implement brave legislation in this context if we are to realise the bold (and morally right) ambition of Smokefree 2025.
2. Second, we must prevent infectious diseases that cause cancer, particularly hepatitis (most cases of Māori liver cancer), helicobacter pylori (most cases of Māori stomach cancer) and human papilloma virus (HPV, nearly all cases of cervical cancer).  Vaccination and test-to-treat programmes exist for many types of these infectious disease: for example, most Kiwi adults (particularly Māori) remain unvaccinated for hepatitis B.  A targeted screening and surveillance programme could identify those with the hepatitis infection, and provide ongoing liver surveillance to find abnormalities early while they are still treatable. 
3. Finally, we must move swiftly away from interventions that focus on people and toward interventions that focus on the system.  The authors of the GBD study categorised factors including tobacco, alcohol use and diet as being ‘behavioural’ in nature, with the inference that reducing these risk factors requires behavioural modification at an individual level.  However, these risk factors have their roots within the social determinants of health, and are strongly patterned by economic and policy factors.  Limiting the availability and accessibility of tobacco, alcohol and non-nutritious foods via regulation is a critical tool available to any country as a means of reducing their likely future burden of cancer.  Focussing on individual behaviour is a red herring pathway that will not lead to this objective. 

Te Aho o Te Kahu – our national Cancer Control Agency – recently published a comprehensive report on cancer prevention, which walks through the known risk factors that matter the most to cancer incidence in Aotearoa New Zealand, and provides clear recommendations regarding systems-level interventions.  While the quick-fire list above is a good starting point, the full report is necessary reading for a full list of the most important things we can do right now to stem the future tide of cancer in this country. 

*Author details: Jason Gurney is part of the Cancer and Chronic Conditions (C3) Research Group, Department of Public Health, University of Otago, Wellington.