Nearly four in every ten cancer cases worldwide could be prevented, according to a major new global analysis released by the World Health Organization (WHO) and its cancer research arm, the International Agency for Research on Cancer (IARC).
Released ahead of World Cancer Day on 4 February, the study estimates that 37% of all new cancer cases recorded globally in 2022 — about 7.1 million cases — were linked to preventable causes. The findings reinforce the critical role of prevention in reducing the growing global cancer burden.
What drives preventable cancer?
Drawing on data from 185 countries and covering 36 different cancer types, the analysis examined 30 preventable risk factors. These include well-known drivers such as tobacco use, alcohol consumption, unhealthy diets, physical inactivity, air pollution and ultraviolet radiation — as well as, for the first time, nine cancer-causing infections.
Globally, tobacco remains the single largest preventable cause of cancer, accounting for 15% of all new cases, followed by infections (10%) and alcohol consumption (3%).
Three cancer types — lung, stomach and cervical cancer — together accounted for nearly half of all preventable cancer cases worldwide in both men and women.
- Lung cancer was mainly linked to smoking and air pollution
- Stomach cancer was largely associated with Helicobacter pylori infection
- Cervical cancer was overwhelmingly caused by human papillomavirus (HPV)
“This is the first global analysis to show how much cancer risk comes from causes we can prevent,” said Dr André Ilbawi, WHO Team Lead for Cancer Control and an author of the study. “By examining patterns across countries and population groups, we can provide governments and individuals with more specific information to help prevent many cancer cases before they start.”
Men, women and regional differences
The burden of preventable cancer was significantly higher in men than in women. Among men, 45% of new cancer cases were linked to preventable causes, compared with 30% among women.
For men globally, smoking alone accounted for 23% of all new cancer cases, followed by infections (9%) and alcohol use (4%). Among women, infections were the leading preventable cause (11%), followed by smoking (6%) and high body mass index (3%).
Preventable cancer rates also varied widely by region. Among women, preventable cases ranged from 24% in North Africa and West Asia to 38% in sub-Saharan Africa. Among men, the highest burden was seen in East Asia (57%), while the lowest was in Latin America and the Caribbean (28%).
“These differences reflect varying exposure to behavioural, environmental, occupational and infectious risk factors, as well as differences in socioeconomic development, national prevention policies and health system capacity,” the report notes.
A case for prevention
“This landmark study is a comprehensive assessment of preventable cancer worldwide,” said Dr Isabelle Soerjomataram, Deputy Head of IARC’s Cancer Surveillance Unit and senior author of the study. “Addressing these preventable causes represents one of the most powerful opportunities to reduce the global cancer burden.”
The report calls for context-specific prevention strategies, including:
- Strong tobacco control and alcohol regulation
- Vaccination against cancer-causing infections such as HPV and hepatitis B
- Improved air quality and safer workplaces
- Healthier food systems and physical activity-friendly environments
WHO and IARC stress that coordinated action across sectors — from health and education to transport, energy and labour — could prevent millions of families from experiencing a cancer diagnosis. Beyond saving lives, prevention also reduces long-term healthcare costs and improves overall population health and wellbeing.
