The World Health Organization (WHO) and its International Agency for Research on Cancer (IARC) state that up to four in ten cancer cases globally can be prevented.
The organizations made this known in a statement on Tuesday, citing a new global analysis.
Released ahead of World Cancer Day on February 4, with the theme “United by Unique”, the analysis estimates that 37% of all new cancer cases in 2022 were linked to preventable causes, representing around 7.1 million cases worldwide.
The study examined 30 preventable causes of cancer, including tobacco use, alcohol consumption, high body mass index, physical inactivity, air pollution, ultraviolet radiation, and—for the first time—nine cancer-causing infections.
“The findings highlight the enormous potential of prevention in reducing the global cancer burden,” the statement said.
Drawing on data from 185 countries and 36 cancer types, the analysis found that tobacco remained the leading preventable cause of cancer, responsible for 15% of all new cases.
Infections accounted for 10%, while alcohol consumption caused 3% of new cancer cases.
It noted that lung, stomach, and cervical cancers made up nearly half of all preventable cancers.
“Lung cancer was primarily linked to smoking and air pollution, stomach cancer was largely attributable to Helicobacter pylori infection, and cervical cancer was overwhelmingly caused by human papillomavirus (HPV),” it said.
Dr André Ilbawi, WHO Team Lead for Cancer Control and an author of the study, said the analysis was the first to show the extent of preventable cancer risks.
“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,” Ilbawi said.
He noted that preventable cancer was significantly higher in men than in women, with 45% of new cancer cases in men compared with 30% in women.
“In men, smoking accounted for 23% of new cancer cases, followed by infections at nine per cent and alcohol at four per cent,” he said.
“Among women globally, infections accounted for 11% of new cancer cases, followed by smoking at six per cent and high body mass index at three per cent.”
Also speaking, Dr Isabelle Soerjomataram, Deputy Head of the IARC Cancer Surveillance Unit and senior author of the study, described the report as a comprehensive assessment of preventable cancer globally.
She said it incorporated infectious causes of cancer for the first time, alongside behavioral, environmental, and occupational risks.
“Addressing these preventable causes represents one of the most powerful opportunities to reduce the global cancer burden,” she said.
Soerjomataram noted that the proportion of preventable cancer varied across regions. Among women, it ranged from 24% in North Africa and West Asia to 38% in sub-Saharan Africa.
“Among men, the highest burden was in East Asia at 57 per cent and the lowest in Latin America and the Caribbean at 28 per cent,” she said.
She explained that these differences reflected varying exposure to risk factors, socioeconomic conditions, national prevention policies, and health system capacity.
“The findings underscore the need for context-specific prevention strategies that include strong tobacco control measures, alcohol regulation, and vaccination against HPV and hepatitis B.
“Others include improved air quality, safer workplaces, and healthier food and physical activity environments,” she said.
Soerjomataram emphasized that coordinated action across sectors could prevent millions from experiencing the burden of cancer.
She added that reducing preventable risks would also lower long-term health costs and improve population well-being.
