Over a Third of New Cancer Cases Worldwide in 2022 Linked to Preventable Factors
A recent international study has indicated that approximately 38% of new cancer cases worldwide in 2022 were attributable to modifiable risk factors. Published in Nature Medicine, the analysis suggests that over seven million cancer diagnoses globally could be potentially preventable through various interventions.
Key Findings
The study reported approximately 19 million new cancer cases globally in 2022, with about 7.1 million of these linked to avoidable causes. Researchers identified tobacco smoking as the primary modifiable contributor to global cancer cases, followed by infections and alcohol consumption.
"Avoiding such risk factors is a significant method to potentially reduce the future cancer burden."
– Hanna Fink, a cancer epidemiologist at the World Health Organization's (WHO) International Agency for Research in Cancer
Primary Modifiable Risk Factors
The analysis identified 30 established modifiable risk factors. The leading contributors to preventable cancer cases included:
- Tobacco Smoking: Accounted for approximately 15% of all cancer cases in 2022. For men, smoking contributed to 23% of new cancer cases globally in that year.
- Infections: Linked to about 10% of new cancer cases.
- Alcohol Consumption: Responsible for 3.2% of new cancer cases, totaling approximately 700,000 cases.
Other modifiable factors included high body mass index, insufficient physical activity, smokeless tobacco, areca nut, suboptimal breastfeeding, air pollution, ultraviolet radiation, and various occupational exposures.
Specific Cancers and Regional Patterns
Lung, stomach, and cervical cancers collectively constituted nearly half of all preventable cancer cases identified in the study.
Cervical Cancer: Among women, high-risk human papillomavirus (HPV) was identified as a primary cause of preventable cancers. An HPV vaccine is available, though global coverage remains low.
Stomach Cancer: More prevalent in men, often associated with smoking and infections linked to overcrowding, inadequate sanitation, and limited access to clean water.
Air Pollution: Its impact varied regionally, accounting for approximately 15% of lung cancer cases in women in East Asia, for example.
"Addressing these preventable causes presents a significant opportunity to decrease the global cancer burden."
– Isabelle Soerjomataram, a medical epidemiologist at WHO and a senior author of the analysis
"Examining patterns across populations can provide governments and individuals with specific information to aid in cancer prevention."
– André Ilbawi, WHO Team Lead for Cancer Control and a co-author
Methodology and Context
Researchers, led by Hanna Fink, analyzed global case data from 2022 for 36 different cancers across 185 countries. This information was combined with 2012 data on people's exposure to each of the 30 identified risk factors to estimate the proportion of cases directly linked to them.
The study's focus on new cancer cases, rather than deaths, and its investigation into multiple risk factors, distinguished it from some previous research that estimated about 44% of global cancer deaths were attributable to avoidable causes.
Cancer remains a leading cause of illness and death globally, with projections indicating an increase in cases if current trends persist. This analysis suggests that millions of cancer cases could be prevented annually through medical intervention, behavioral modifications, reduction of occupational hazards, and mitigation of environmental pollutants.