Over the last decades, cancer incidence has been increasing in Europe, being cancer one the leading causes of death. Meaningful differences persist in cancer incidence and mortality between Western and Eastern European countries, highlighting regional differences regarding risk factors (e.g., smoking habits). Cancer Primary Prevention (CPP) aims to tackle these modifiable factors and to decrease individual risk of cancer. Yet, implementing CPP goes beyond the actions of the governments, and involves a complexity of actions from different stakeholders in society. In this study, we use mixed methods to characterize CPP stakeholders of public sector, academia/research, private sector, media and civil society. We also aim to get a deeper understanding on the regional differences in cancer incidence and mortality. Descriptive statistics were performed to analyze survey results - relative frequencies (%) were computed for each variable, and are presented for the total sample and stratified by country group (Western and Eastern). Data from interviews were analyzed by thematic analysis

Backgroung: -Cancer remains a major public health concern, being associated with meaningful mortality, disability and economic costs. -Upward trend in the number of new cases of cancer in Europe. -Cancer Primary Prevention is cost-beneficial approach with a large potential of reducing incidence and mortality. - Individual lifestyle actions (e.g., smoking cessation). -○ Regulatory actions (e.g., taxation of beverages) -Other policies at the populational level (e.g., reducing air pollution) - The full potential of cancer primary prevention does not seem to be developed.

Background: 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% of all cancers are preventable, public awareness of modifiable risk factors remains low. The European Code Against Cancer (ECAC), developed under the World Code Against Cancer Framework, aims to strengthen prevention knowledge; however, tools to measure cancer prevention literacy, and therefore evaluate its impact, are lacking. This study aimed to develop and validate a questionnaire to assess ‘cancer prevention literacy’ in adults from the general population. Methods: We conducted a methodological study to develop a questionnaire measuring ‘cancer prevention literacy’ in adults from the general population using the Integrative Model of Behavioural Prediction as theoretical framework. Questionnaire development followed a three-stage process: (1) a literature review and two-round Delphi process to select and refine items; (2) a third Delphi round, complemented by readability checks, face-validity assessment, and cognitive testing to evaluate item relevance, clarity, and representativeness; and (3) a pre-test and psychometric analysis to assess construct validity. Results: The final Cancer Prevention Literacy Questionnaire (CPL-Q) consists of a 10-question validated instrument comprising 58 items, with selected items incorporating the verbatim wording of the recommendations from the ECAC, 4th edition. Strong expert agreement was achieved through an iterative Delphi process, and content and face validity indicated that the items were comprehensible, relevant, and appropriate. Psychometric analyses, including exploratory and confirmatory factor analysis, provide preliminary support for the instrument’s construct validity, with initial evidence suggesting acceptable reliability. Conclusion: The CPL-Q provides a standardised instrument to measure ‘cancer prevention literacy’ and to assess the impact of Regional Codes Against Cancer through monitoring and benchmarking changes over time. It also offers a practical tool to identify gaps in ‘cancer prevention literacy’ within specific populations and to support international comparisons and longitudinal evaluations, thereby contributing to the evidence base for cancer prevention policies.