Over the past 6 decades, the International Agency for Research on Cancer (IARC) has played a pivotal role in global cancer research capacity building. This study presents a comprehensive evaluation of IARC's capacity-building initiatives with a mixed-methods approach. We integrated qualitative and quantitative data from institutional records, outcome surveys, and a career-tracking study of postdoctoral fellows. IARC's capacity-building portfolio includes fellowships, digital-learning platforms, a summer school, and global networks such as the Global Initiative for Cancer Registry development, the Cancer Screening in 5 Continents project, and the Biobank and Cohort Building Network. Since 1966, approximately 30 000 professionals from most countries in the world have benefited from those initiatives, with a majority from low- and middle-income countries. Among tracked IARC postdoctoral fellows, since 1966, 76.5% remained in academia, and 18.7% had a role in public health policy. Qualitative findings highlight the impact of IARC training on individual careers, institutional capacity, and global cancer control strategies. IARC's sustained investment in capacity-building has strengthened the cancer research workforce and institutional infrastructures while reducing inequalities in low- and middle-income countries. These efforts have advanced leadership, equity, and evidence-based cancer prevention. As global health challenges evolve, continued support remains essential to achieving equitable cancer control worldwide.

Prevention and early detection are central to reducing the global cancer burden, yet implementation remains uneven, particularly in low- and middle-income countries. This narrative review synthesizes the contributions of the International Agency for Research on Cancer (IARC) to translating evidence into policy and practice worldwide across vaccination, screening, and early diagnosis. Key advances include generating evidence that enabled the World Health Organization (WHO) recommendation of single-dose human papillomavirus vaccination; contributions to WHO Elimination of Cervical Cancer Initiative and Global Initiative on Breast Cancer; development of guidance for Helicobacter pylori screen-and-treat strategies; building decision platforms to optimize cost-effective strategies; and establishing CanScreen5 to benchmark cancer screening program performance globally. IARC led European Union screening status reports, codeveloped quality-assurance schemes, and standardized performance indicators. Through implementation research, capacity-building, and codesigned solutions, IARC supports prostate, gastric, and lung cancer screening pilots and equity-oriented approaches that strengthen health-care systems. By embedding evidence, modeling, and governance, IARC helps countries transition from pilots to population-level impact, accelerating progress toward WHO targets and equitable outcomes in cancer control.

Health literacy is a key determinant of health, shaping individuals ability to understand and act on health information. Low cancer literacy is associated with fatalistic beliefs and reduced participation in prevention and screening programmes. Although around 40

Diet, body weight, physical activity, sedentary behavior, and breastfeeding are modifiable factors influencing the cancer burden in the European Union, shaped by underlying social, commercial, environmental, and behavioral conditions. Excess body weight has reached epidemic levels, significantly influenced by widespread intake of sugar-sweetened beverages and ultra-processed foods rich in sugar, fat, and salt. Consumption of red and processed meat also commonly exceeds dietary recommendations. Physical inactivity and prolonged sedentary behavior are widespread. Breastfeeding rates vary widely across Europe but are generally low, particularly in high-income countries. To reduce cancer risk, the European Code Against Cancer, 5th edition (ECAC5) recommends a diet rich in whole grains, vegetables, legumes, and fruits, while limiting red meat and avoiding processed meat. Intake of vegetables, legumes, and fruits prevents aerodigestive tract cancers, while diets high in whole grains and low in red and processed meat reduce colorectal cancer risk. Avoiding excess body weight through diet and physical activity, and limiting prolonged sitting, decreases risk of numerous cancers. Promoting and supporting sustained breastfeeding contributes to lowering breast cancer risk. Key policy interventions, such as fiscal incentives, urban planning, marketing restrictions, and public awareness campaigns, are central to creating supportive environments for cancer prevention.

Knowledge mobilisation is essential in cancer prevention to equip individuals with the knowledge to reduce their risk and improve their health. Hence, dissemination of evidence-based recommendations is a key tenet in the fight to reduce the burden of cancer in the European Union (EU). Systems thinking was used to guide the methods of three substudies involving stakeholders in identifying dissemination actions to enhance the awareness and uptake of the European Code Against Cancer, 5th edition (ECAC5), including mapping barriers and facilitators to achieve impactful dissemination. The proposed actions aimed to foster collaboration and partnership across diverse sectors, utilising diverse and accessible channels to deliver visually engaging content to maximise the delivery and impact of the ECAC5 to the general public in the EU. Many of these actions were evaluated by participants as highly feasible and impactful, thereby supporting their implementation.

Occupational exposure to cancer-causing agents is a major, yet preventable, contributor to cancer in Europe and globally. In the European Union (EU), cancer is responsible for nearly half of all work-related deaths, underscoring the critical need for prevention measures. Effective strategies typically involve regulatory and workplace measures aimed at reducing or eliminating exposure risks. Raising awareness of hazardous workplace exposures is essential to empower individuals, foster a culture of prevention, and support effective regulation. The 5th edition of the European Code Against Cancer (ECAC5) includes a recommendation on how individuals can minimize their cancer risk and highlights the shared responsibilities of workers and employers for occupational safety and health: 'Inform yourself about cancer-causing factors at work and call on your employer to protect you against them. Always follow health and safety instructions at your workplace'. Key to ECAC5 is the addition of policy pointers at the governance level to support employers in taking preventive action and improving worker awareness. Strengthening regulatory frameworks and increasing awareness are crucial steps toward reducing the burden of occupational cancer.

Cancer primary prevention (CPP), particularly through evidence-based recommendations like the 4th European Code Against Cancer (ECAC4), represents a cost-effective strategy to reduce cancer burden. Dissemination and implementation (D I) of CPP strategies remain fragmented and inconsistent, and instruments to assess dissemination of CPP are lacking. This study aimed to develop and validate an instrument to assess the public (i) perceptions of CPP message characteristics, and (ii) public perceptions of ECAC4. The validation of the ´Information on Cancer Primary Prevention` instrument was developed through a multi-stage process grounded in two D I frameworks: McGuire’s Communication-Persuasion Matrix and Rogers’ Diffusion of Innovations. After literature review, items were generated for the two questions assessing message characteristics (channel preferences and source trustworthiness) and 25 items to assess ECAC4 five perceived attributes: advantage, compatibility, complexity, trialability, and observability. Validation involved cognitive interviews for message characteristics, expert validation through a two-round Delphi panel for ECAC4 attributes, and pre-testing with 240 adults recruited through an online panel. Exploratory factor analysis (EFA) was conducted to assess structural validity, and Cronbach’s alpha was used to evaluate internal consistency. Refinements in terminology, response scales, and item wording were implemented after cognitive interviews for the two questions of message characteristics (channel preference and source trustworthiness). EFA revealed three factors for channel preferences (Traditional broadcast media, Digital media/online interactive platforms, and Print media and interpersonal; α = 0.703–0.775) and two factors for source trustworthiness (Official sources and Unofficial sources; α = 0.792–0.859). The five ECAC4 attributes were evaluated in a Delphi panel with two rounds - due to participant attrition the panel was discontinued before full consensus could be reached for all items; five items were adapted based on expert qualitative feedback and included in the pre-test. All five ECAC4 attributes subscales demonstrated unidimensionality with strong factor loadings (> 0.50) and good to excellent reliability (α = 0.714–0.831). This instrument exhibits initial evidence of content and exhibits satisfactory psychometric properties, offering preliminary evidence of structural validity, and internal consistency. By operationalizing key constructs from established dissemination and implementation frameworks, it addresses critical gaps in cancer prevention communication research.

Most European Union (EU) residents live in areas where outdoor air pollution levels exceed the 2021 World Health Organization (WHO) air quality guidelines for fine particles and nitrogen dioxide. Outdoor air pollution is classified as carcinogenic to humans, and both outdoor and indoor air contain established human carcinogens, including diesel exhaust particulates, benzo(a)pyrene [B(A)P] and benzene. The European Code Against Cancer, 5th edition (ECAC5), incorporates recommendations for individuals and policymakers aimed at reducing the cancer burden from both outdoor and indoor air pollution. A critical step is aligning EU air quality limit values with the more stringent 2021 WHO guidelines. This should be complemented by integrated policy measures, including stricter regulation of combustion emissions, promotion of active and environmentally friendly transportation, incentives for cleaner energy sources for heating and cooking, and harmonization with broader EU climate initiatives. At the individual level, emissions and exposure may be reduced by limiting car use, avoiding second-hand smoke, and refraining from burning wood or coal indoors or outdoors. Further exposure reduction may be achieved by limiting walking or cycling along heavily trafficked routes.

The main infections that cause cancer in the European Union (EU) are Helicobacter pylori (H. pylori), human papillomavirus (HPV), hepatitis B virus (HBV), hepatitis C virus (HCV) and human immunodeficiency virus (HIV). Altogether, in 2022, these infections accounted for ~ 5% of all cancers in the EU, mainly of the stomach, cervix uteri and liver. The largest burden of infection‐caused cancers was found in the south of the EU and near the eastern border. Substantial progress in the efficacy of interventions against these infections has been made since the release of the 4th edition of the European Code Against Cancer in 2015. Cancers due to infections can increasingly be prevented by prophylactic vaccines (HPV and HBV) and/or prompt diagnosis and treatment that can either cure (HCV and H. pylori) or slow down the infection (HBV and HIV), thus substantially reducing disease risk. Tools to tackle carcinogenic infections are also increasingly accessible and affordable in the EU, but their implementation is slow. Public awareness, political will and cost‐effective protocols are necessary to establish large programmes of vaccination or testing and treatment. Progress monitoring, as well as avoiding disinformation and stigma, is crucial to ensure that advances in medical progress are fully leveraged. The recently published 5th edition of the European Code Against Cancer therefore recommends: (1) vaccinate girls and boys against HBV and HPV at the age recommended in your country; (2) take part in testing and treatment for HBV and HCV, HIV and H. pylori, as recommended in your country.

The 5th edition of the European Code Against Cancer (ECAC5) recommends sustainable, organised screening programmes for: (a) colorectal cancer using biennial quantitative faecal immunochemical test (FIT) for individuals aged 50–74 years. As an alternative strategy, once‐only endoscopy may be considered within the same age range; (b) breast cancer using biennial digital mammography for women aged 50–69 years. Implementing this strategy for women aged 45–49 years and 70–74 years can be considered. Other screening strategies or additional examinations could be considered for women with high mammographic density; (c) cervical cancer using human papillomavirus (HPV) screening at intervals no shorter than 5 years for women aged 30–65 years. It is recommended to adapt policies according to vaccination status and screening history; and (d) lung cancer using annual low‐dose computed tomography (LDCT) for individuals considered to be at increased risk of lung cancer based on age, history of smoking or validated risk models, with biennial screening as an alternative. Screening should incorporate smoking cessation interventions.

Tobacco use, second-hand tobacco smoke (SHS) exposure and alcohol consumption are well-established carcinogens and major public health concerns. In the European Union (EU), tobacco and alcohol use are the leading preventable causes of cancer and four other major noncommunicable diseases (NCDs), significantly contributing to NCD-related morbidity and mortality. Despite declining prevalence, consumption of these substances is still high in the region, especially among the most deprived. There is strong evidence that quitting smoking, minimising exposure to SHS and eliminating or reducing alcohol intake substantially lowers the risk of cancer. Comprehensive public health strategies at both the individual and population level are crucial to prevent cancer and other NCDs. Scientific evidence leads to two recommendations for individual action on tobacco in the European Code Against Cancer, 5th edition: (1) ‘Do not smoke. Do not use any form of tobacco, or vaping products. If you smoke, you should quit’; and (2) ‘Keep your home and car free of tobacco smoke’; and one on alcohol: (3) ‘Avoid alcoholic drinks’.

The European Code Against Cancer (ECAC) provides evidence-based recommendations to help individuals reduce their cancer risk. For the 5th edition (ECAC5), recommendations on ultraviolet radiation (UVR) and indoor radon exposures were updated, and complementary recommendations for policymakers were introduced. UVR and radon are classified as carcinogenic to humans (group 1 carcinogens) in the International Agency for Research on Cancer (IARC) Monographs. Solar UVR and, to a lesser extent, artificial forms of UVR exposure are major causes of skin cancer, while radon gas is a leading cause of lung cancer. This paper summarises the evidence for retaining and refining these recommendations. For individuals, ECAC5 advises avoiding excessive sun exposure, especially in children, using sun protection, and never using sunbeds; for radon, checking local radon maps, seeking professional measurement where appropriate and taking remedial action, if necessary, are recommended. For policymakers, ECAC5 encourages harmonised UVR protection measures across the European Union, enforcement of regulations concerning indoor tanning devices, and enabling access to testing of radon levels, and support for mitigation and remediation. These recommendations provide actionable, evidence-based recommendations to help reduce cancer risk and align with Europe's Beating Cancer Plan.

The European Code Against Cancer (ECAC) provides evidence-based recommendations to help individuals reduce their cancer risk. For the 5th edition (ECAC5), recommendations on ultraviolet radiation (UVR) and indoor radon exposures were updated, and complementary recommendations for policymakers were introduced. UVR and radon are classified as carcinogenic to humans (group 1 carcinogens) in the International Agency for Research on Cancer (IARC) Monographs. Solar UVR and, to a lesser extent, artificial forms of UVR exposure are major causes of skin cancer, while radon gas is a leading cause of lung cancer. This paper summarises the evidence for retaining and refining these recommendations. For individuals, ECAC5 advises avoiding excessive sun exposure, especially in children, using sun protection, and never using sunbeds; for radon, checking local radon maps, seeking professional measurement where appropriate and taking remedial action, if necessary, are recommended. For policymakers, ECAC5 encourages harmonised UVR protection measures across the European Union, enforcement of regulations concerning indoor tanning devices, and enabling access to testing of radon levels, and support for mitigation and remediation. These recommendations provide actionable, evidence-based recommendations to help reduce cancer risk and align with Europe's Beating Cancer Plan.

Tobacco use, second-hand tobacco smoke (SHS) exposure and alcohol consumption are well-established carcinogens and major public health concerns. In the European Union (EU), tobacco and alcohol use are the leading preventable causes of cancer and four other major noncommunicable diseases (NCDs), significantly contributing to NCD-related morbidity and mortality. Despite declining prevalence, consumption of these substances is still high in the region, especially among the most deprived. There is strong evidence that quitting smoking, minimising exposure to SHS and eliminating or reducing alcohol intake substantially lowers the risk of cancer. Comprehensive public health strategies at both the individual and population level are crucial to prevent cancer and other NCDs. Scientific evidence leads to two recommendations for individual action on tobacco in the European Code Against Cancer, 5th edition: (1) 'Do not smoke. Do not use any form of tobacco, or vaping products. If you smoke, you should quit'; and (2) 'Keep your home and car free of tobacco smoke'; and one on alcohol: (3) 'Avoid alcoholic drinks'.

Although cancer is a leading cause of death in the European Union, around 40% of cases are preventable. The European Code Against Cancer (ECAC) was developed to inform citizens about key cancer‐risk‐reducing actions. This study aimed to identify effective ways to present the 5th edition of the code (ECAC5) to optimise awareness of cancer risks in all socioeconomic groups. Using a 2 × 3 × 2 factorial design, 10 027 participants from eight countries were randomised online to receive ‘no message’ or one of 10 ECAC5 formats differing in message content (cancer risks: present/absent), length of message on cancer prevention actions (longer/shorter/absent) or format (text‐only/text with images). The primary outcome was awareness of 16 avoidable cancer risks. Overall mean number of risks recalled was 2.40 (standard deviation: 1.72; range 0–14). Recall was highest when messages included risk information. Adding prevention messages to risk information did not improve risk factor recall. Message length and images had no significant impact. Effects were similar across levels of education and countries. Combined information about risk factors and preventive actions has the potential to equitably increase citizens’ very low cancer prevention awareness. How this awareness might change over time or lead to behaviour change is unknown and should be the focus of future evaluations.

The European Code Against Cancer (ECAC) provides evidence‐based public health recommendations to reduce cancer risk across Europe. First launched in 1987, it is periodically updated mainly to reflect scientific advances. The 5th edition (ECAC5), released for the medical oncology community in 2025 and to be presented to the public in 2026, aims to offer an authoritative and practical tool for cancer prevention for individuals and policymakers. Developed by over 60 experts across five Working Groups, ECAC5 expands the 12 recommendations of the 4th edition to 14, incorporating the latest evidence on modifiable cancer risks and effective medical interventions. Key innovations include new guidance on air pollution, cancer‐related infections, lung cancer screening and strengthened recommendations on tobacco, alcohol, diet, body weight, and occupational and radiation exposures. A major advancement is the addition of dedicated policy recommendations, acknowledging that many prevention measures require supportive environments and regulation. By aligning cancer prevention with broader noncommunicable disease strategies, ECAC5 aims to enhance uptake and impact. Its effective implementation could prevent up to 40% of new cancers in the EU.

Diet, body weight, physical activity, sedentary behavior, and breastfeeding are modifiable factors influencing the cancer burden in the European Union, shaped by underlying social, commercial, environmental, and behavioral conditions. Excess body weight has reached epidemic levels, significantly influenced by widespread intake of sugar-sweetened beverages and ultra-processed foods rich in sugar, fat, and salt. Consumption of red and processed meat also commonly exceeds dietary recommendations. Physical inactivity and prolonged sedentary behavior are widespread. Breastfeeding rates vary widely across Europe but are generally low, particularly in high-income countries. To reduce cancer risk, the European Code Against Cancer, 5th edition (ECAC5) recommends a diet rich in whole grains, vegetables, legumes, and fruits, while limiting red meat and avoiding processed meat. Intake of vegetables, legumes, and fruits prevents aerodigestive tract cancers, while diets high in whole grains and low in red and processed meat reduce colorectal cancer risk. Avoiding excess body weight through diet and physical activity, and limiting prolonged sitting, decreases risk of numerous cancers. Promoting and supporting sustained breastfeeding contributes to lowering breast cancer risk. Key policy interventions, such as fiscal incentives, urban planning, marketing restrictions, and public awareness campaigns, are central to creating supportive environments for cancer prevention.

Occupational exposure to cancer-causing agents is a major, yet preventable, contributor to cancer in Europe and globally. In the European Union (EU), cancer is responsible for nearly half of all work-related deaths, underscoring the critical need for prevention measures. Effective strategies typically involve regulatory and workplace measures aimed at reducing or eliminating exposure risks. Raising awareness of hazardous workplace exposures is essential to empower individuals, foster a culture of prevention, and support effective regulation. The 5th edition of the European Code Against Cancer (ECAC5) includes a recommendation on how individuals can minimize their cancer risk and highlights the shared responsibilities of workers and employers for occupational safety and health: ‘Inform yourself about cancer-causing factors at work and call on your employer to protect you against them. Always follow health and safety instructions at your workplace’. Key to ECAC5 is the addition of policy pointers at the governance level to support employers in taking preventive action and improving worker awareness. Strengthening regulatory frameworks and increasing awareness are crucial steps toward reducing the burden of occupational cancer.

Background:Cancer prevention is central to Europe's Beating Cancer Plan (ECBP), with the European Code Against Cancer (ECAC) providing evidence-based recommendations to reduce cancer risk. The fourth edition (ECAC4) focuses on individual behaviour change, but effective implementation requires insight into individual and structural factors influencing adoption. We explored barriers and facilitators to adopting ECAC4 recommendations across nine EU Member States to inform the forthcoming edition. Methods:An exploratory multi-country qualitative study with 141 adults aged 18-65 years, with no prior cancer diagnosis, from Bulgaria, Croatia, France, Germany, Ireland, Poland, Portugal, Romania, and Spain was conducted. Semi-structured interviews examined perceived capability, opportunity, and motivation related to the 12 ECAC4 recommendations. Transcripts were translated, coded, and thematically analysed using ATLAS.ti, with high intercoder agreement (κ = 0.88). Themes were mapped onto the COM-B and Theoretical Domains Framework (TDF) to identify behavioural determinants. Findings:Barriers and facilitators were identified across all COM-B domains. Capability barriers included low health literacy, misinformation, and limited self-management skills; facilitators included early health education and reliable information. Opportunity barriers encompassed cultural norms, economic constraints, environmental limitations, and healthcare access issues; facilitators included supportive social networks, universal healthcare, and enabling policies. Motivation barriers involved entrenched habits and fear, while facilitators included personal health goals, family responsibilities, and determination. Interpretation:Adoption of ECAC4 recommendations is shaped by interlinked individual, social, and structural determinants. Multi-level implementation strategies, improving health literacy, ensuring equitable access, strengthening supportive environments, and tailoring motivational approaches, are essential. These findings directly inform ECAC5 and support the objectives of ECBP. Funding:This project was funded by the Cancer Prevention Europe (CPE) consortium and additionally supported by the budget of IARC's Environment and Lifestyle Epidemiology Branch.

Despite the growing cancer burden in the European Union, public awareness of effective prevention is low. In response, Europe's Beating Cancer Plan has supported the development of the 5th edition of the European Code Against Cancer (ECAC5). Using a transparent, stepwise decision-making process, around 80 experts reviewed the latest scientific evidence on cancer prevention and used modern communication strategies to update the previous edition. An innovation in ECAC5 is the inclusion of population-level recommendations, aiming to structurally influence the systems that shape individual choices and improve environmental conditions to which all citizens are involuntarily exposed. ECAC5 includes 14 actionable, evidence-based recommendations for individuals to reduce their cancer risk alongside their respective policy recommendations. All are presented through equity lens, with attention to co-benefits for preventing other non-communicable diseases and tailoring messages to diverse audiences. Clear evidence-based statements on cancer risks factors and effective preventive interventions will empower citizens to make healthier choices, call policymakers to act, foster public support for effective policies, and contribute to more effective cancer prevention.