A cancer registrar plays a critical role in supporting cancer prevention, diagnosis, treatment, and research. They work in a variety of environments, such as hospitals, clinics, cancer registries, government agencies, or pharmaceutical companies. Their responsibilities include identifying and registering cancer cases from medical records, pathology reports, and other sources. They must also abstract and code relevant data such as patient demographics, tumor characteristics, staging, treatment, and outcomes. Cancer registrars are responsible for ensuring the accuracy, completeness, and timeliness of the data. Additionally, they must report the data to state or national cancer registries as well as other authorized users while maintaining the confidentiality and security of the data. Furthermore, they must perform quality control and audits to verify the data and participate in research and education activities related to cancer epidemiology, surveillance, and control.