Objectives	To describe: A population-based cancer registry and its key functions The relevance of cancer registry data in cancer control
Key Concepts	Recognise that population-based cancer registries capture a standardised minimum data set about the person, the malignancy, the treatment and the outcome Demonstrate an understanding that population-based registries with high completeness and good data quality provide an unbiased picture of cancer epidemiology in their territory Demonstrate an understanding that population-based registries combine data about each patient from many health care facilities to create a unique database of all residents in their territory who are diagnosed with a registrable malignancy Demonstrate an understanding that most registries follow up with all registered patients to establish their vital status (alive, dead, lost to follow-up, emigrated) on a regular basis, and that these data are used to estimate population-based cancer survival Demonstrate an understanding that cancer registration is a statutory requirement in many countries, and be aware of the position in your own country Explain why hospital-based registries provide valuable information about the patients managed in that hospital (eg, caseload, investigations, follow-up, case-fatality ratios), but cannot usually provide a representative profile of cancer in the country or region where they are located Define a cancer incidence rate as the number of persons diagnosed with a registrable malignancy in a given country or region (state, province, etc) in a given calendar year, typically expressed per 100,000 population per year Define a cancer mortality rate as the number of persons certified as having died with cancer as the underlying cause of death (a specific cancer or all cancers combined) in a given country or region, again per 100,000 population per year Demonstrate an understanding that cancer survival is estimated as a probability (in the range 0-1) from population-based data. Understand that survival estimates are usually expressed as percentage in the range 0%-100%, for convenience Recognise that survival estimates are only meaningful if the period when the patients were diagnosed and the duration of survival is stated (eg, the estimated 5-year survival of patients diagnosed during 2015-2019 was 75%) Demonstrate an understanding that net survival is a population-based metric that reflects the survival of all patients in a country or territory, after correction for the risk of death from other causes, given that this competing risk of death is higher in elderly persons Demonstrate an understanding that registries routinely publish cancer incidence and survival statistics for their territory by age, sex and calendar year, often by other variables such as stage at diagnosis, race/ethnicity, and socio-economic status Define a case-fatality ratio as the proportion of persons diagnosed with a cancer who die within a specified period of time, usually a few weeks or months Demonstrate an understanding why the mortality-to-incidence ratio (M/I ratio) is not a case-fatality ratio, and why the complement of the M/I ratio (1-M/I) is not a valid proxy for survival Recognise that registries maintain the confidentiality and security of their data with electronic, physical, and managerial arrangements designed to reduce the risk of inadvertent disclosure to the absolute minimum Demonstrate an understanding that population-based registries are a unique resource for research into the causes, incidence, management, and survival of patients with cancer, and into the quality of life of survivors (survivorship research) Recognise why ethical or statutory approval is usually required for observational research using registry data without patient consent Demonstrate an understanding why cancer registry data are an essential component of rational cancer control policy Give examples of how cancer registry data have been deployed to formulate cancer control policies (eg, early diagnosis, screening, access to health care), and subsequently to evaluate the impact of those policies
Skills	Demonstrate the ability to: Use cancer registry data to describe current patterns and past trends of incidence and survival in your country or region, or in a sub-group of the population Interpret graphs and tables from registry data appropriately, to gain insight into the adequacy of cancer control plans and intervention programmes Report information derived from cancer registry data accurately and in appropriate language to policy-makers, to advocate for relevant policy initiatives