Up to four in 10 cancer cases worldwide could be prevented by reducing exposure to known risk factors, according to a new analysis from the World Health Organization (WHO) and its cancer research agency, reinforcing prevention and early detection as central pillars of cancer control as incidence continues to rise globally.
“This is the first global analysis to show how much cancer risk comes from causes we can prevent,” says André Ilbawi, Team Lead for Cancer Control, WHO, referring to the scale of evidence now available to guide public policy and individual action ahead of World Cancer Day on Feb. 4.
The analysis, conducted by WHO and the International Agency for Research on Cancer, examined 30 preventable causes of cancer across 185 countries and 36 cancer types. It estimates that 37% of all new cancer cases diagnosed in 2022, or about 7.1 million cases, were linked to preventable factors. These include tobacco use, alcohol consumption, high body mass index, physical inactivity, air pollution, ultraviolet radiation, and cancer-causing infections.
Tobacco was identified as the leading preventable cause, responsible for 15% of new cancer cases worldwide. Infections followed at 10%, while alcohol consumption accounted for 3%. Lung, stomach, and cervical cancers together represented nearly half of all preventable cancer cases globally. Lung cancer was primarily associated with smoking and air pollution, stomach cancer with Helicobacter pylori infection, and cervical cancer with human papillomavirus.
The burden of preventable cancer varied significantly by sex and region. Preventable causes accounted for 45% of new cancer cases among men, compared with 30% among women. In men, smoking alone was linked to an estimated 23% of new cases, followed by infections and alcohol. Among women, infections were the leading preventable cause, followed by smoking and high body mass index. Regionally, preventable cancer among women ranged from 24% in North Africa and West Asia to 38% in sub-Saharan Africa, while among men the highest proportion was observed in East Asia at 57% and the lowest in Latin America and the Caribbean at 28%. WHO and IARC say these differences reflect variations in exposure to risk factors, socioeconomic conditions, prevention policies, and health system capacity.
Isabelle Soerjomataram, Deputy Head, IARC’s Cancer Surveillance Unit, says addressing preventable causes represents one of the most direct opportunities to reduce the global cancer burden. WHO and IARC add that responses must be tailored to national and regional contexts and include strong tobacco control, alcohol regulation, vaccination against cancer-causing infections such as HPV and hepatitis B, improved air quality, safer workplaces, and healthier food and physical activity environments.
The findings were released as part of the World Cancer Day 2025–2027 campaign, themed “United by Unique,” which places people and their lived experiences at the center of cancer care. Campaign organizers argue that cancer is not only a biological disease but also a long-term condition with mental, social, and economic consequences. They say traditional oncology models often focus narrowly on symptoms and treatment, overlooking social determinants such as income, education, living conditions, and access to support, which shape outcomes and recovery.
The campaign calls for a people-centered approach that integrates prevention, early detection, treatment, survivorship, and end-of-life care, while actively involving patients, caregivers, and communities in shaping services and policies. WHO says that coordinated action across sectors, including health, education, energy, transport, and labor, is required to reduce cancer risk and improve outcomes.
The emphasis on prevention comes as cancer incidence continues to rise worldwide. WHO estimates that 20 million new cancer cases were diagnosed globally in 2022, resulting in 9.7 million deaths. According to Guillaume Corpart, Founder and CEO, Global Health Intelligence, this trend reflects a complex outlook. While rising incidence increases demand for diagnostics, treatment and long-term monitoring, declining mortality rates in several cancers point to gains from earlier detection and improved therapies. Breast cancer deaths, for example, have been reduced by nearly half since the mid-1970s, and five-year survival rates now reach about 90% in developed markets.
These dynamics are reshaping health systems and markets. The global oncology market is projected to grow at an annual rate of nearly 11% over the next decade, with cancer medicine spending expected to rise sharply. Yet disparities persist. Latin America accounts for a small share of global oncology spending, highlighting gaps in access to diagnostics, treatment, and advanced technologies. Corpart said addressing these disparities will require not only innovation but also sustained investment in prevention, screening, and infrastructure.
Mexico illustrates how prevention, system capacity, and innovation intersect. Authorities have expanded HPV vaccination as part of efforts to prevent cervical and other HPV-related cancers. The State of Mexico, for example, has provided free HPV vaccines through health centers under the 2025 national vaccination campaign, which extended coverage to boys for the first time and targeted adolescents, survivors of sexual violence, and people living with HIV. Health officials say the initiative aligns with WHO and Pan American Health Organization (PAHO) goals to eliminate cervical cancer through vaccination, screening and treatment.
WHO and IARC have also launched a global training program through the WHO Academy to strengthen screening, diagnosis, and management of cervical precancer. The program supports countries working toward the 90–70–90 targets for cervical cancer elimination by 2030, which include vaccinating 90% of girls against HPV, screening 70% of women with high-performance tests, and treating 90% of women diagnosed with disease. In Mexico, health authorities report that most women treated in public institutions still arrive with advanced-stage cervical cancer, underscoring the need for workforce training and early detection.
Mexico’s National Institute of Cancerology (INCan) has increased its focus on early detection for cancers with high mortality when diagnosed late. The institute has called on men aged 40 and older to seek prostate cancer screening and has expanded training for primary care physicians to improve first-contact diagnosis. INCan reports that more than 70% of prostate cancer cases it receives are already at advanced stages, limiting treatment options.
At the same time, INCan is expanding care capacity as demand grows. In 2024, it delivered more than 318,000 oncology consultations and expects to register over 8,300 new patients for first-time care in 2025. The institute has added precision radiotherapy, robotic surgery, and expanded academic partnerships, while operating under a gratuity model that covers surgery, radiotherapy, and medications, including targeted therapies and immunotherapy.
Innovation is advancing alongside these system-level efforts. Researchers at the Universidad Nacional Autónoma de México have developed therapeutic vaccines for breast cancer that eliminate tumors and metastases in laboratory models, positioning the project for future clinical trials. The vaccines are designed to activate immune responses against evolving cancer cells and could complement existing treatments if validated in humans.
Digital health technologies are also playing a growing role. Companies such as Eden are deploying AI-assisted diagnostic platforms across Latin America to address shortages of specialists, reduce diagnostic errors, and shorten turnaround times. Eden’s cloud-based platform integrates tele-diagnosis and AI models trained on regional data to improve early detection, including for lung cancer, where early diagnosis significantly improves survival.
WHO and IARC say prevention, early detection, innovation, and people-centered care must advance together. They argue that reducing exposure to preventable risk factors not only lowers cancer incidence but also eases long-term pressure on health systems, improves population health, and supports more sustainable cancer care models as demand continues to grow worldwide