Cancer registries provide information to clinicians and other healthcare providers, public health officials, administrators, and scientists for a variety of purposes. Their ultimate goal is to prevent and control cancer, including improvement of cancer patient care. 23 Since 1956, the American College of Surgeons has required all approved cancer programs to establish a cancer registry which can “measure the quantity and quality of medical care provided for cancer patients at a given institution.” Further, “the hospital cancer registry has been described as the “mirror” which can reflect to the hospital staff how well it is diagnosing and treating cancer in its hospital”. 24 The American Cancer Society expanded on this by enumerating four basic activities: 25
- To provide quality control information on the diagnosis and treatment of cancer.
- To perform follow-up processes to accumulate time-mortality data for assessing end results.
- To provide education of clinicians in the diagnosis of cancer.
- To provide a repository of bio-statistical data for research.
Today’s hospital cancer registry retains this description 45 years later, adding to its activities support for administrators, cancer control, and other public health programs.
Central cancer registries collect cancer information for the population residing in a defined-geographic location, usually a state or province. The uses of central cancer registry data include: 26
- Assessment of disease occurrence using rates;
- Calculation and assessment of survival estimates;
- Epidemiologic research and program support; and
- Cancer control activities
In addition to state-level cancer registries, federal/national cancer registry programs also exist to monitor the burden of cancer in the county/nation.
In the mid-1990s the cancer registry community, consisting of central and hospital registry standard setters, developed data standards for the electronic transmission of cancer abstract reports. These data standards allow for the electronic transmission of cancer abstract reports between the different registry software actors, e.g. hospital and central cancer registries, and national cancer registry programs. The data standards are updated on an annual basis as new data items and value sets are introduced and existing ones are modified or deprecated.
Cancer registries rely heavily on the anatomic pathology laboratory as it serves as the central source for identifying and confirming reportable cancer cases. Additionally, the pathology report is the primary medical report that provides the majority of the diagnostic information about the patient’s cancer. The most important information in the pathology report includes the source of the specimen, primary site, size of the tumor, histologic type and the grade of cancer, and stage/extent of disease progression. The results of additional clinical testing such as cytogenetics and molecular markers may also be provided within the pathology report. Cancer registries have developed standards for electronically transmitting pathology reports to a cancer registry, making the information available to the registry and its users in near real-time. 27,28 The cancer registry community has also developed standards for the interpretation of pathology reports where the degree of suspicion or level of certainty is not clearly apparent. Diagnostic terminology or modifiers are defined as being either considered as diagnostic of cancer or not. For example, a cancer which is described as presumed or probably cancer is considered diagnostic of cancer (reportable), while a diagnosis with the terms possible or suggestive of is not. 29 While the cancer registry community has a consistent standard for interpreting the degree of suspicion, radiologists and pathologists did not contribute to this standard and do not use it in their practice.
The diagnostic radiology/imaging department also serves as an important source in providing information to the cancer registry as radiologic procedures (e.g. x-ray, CT and bone scans) complement the pathology report in order to provide a more complete picture of the extent of cancer progression (stage) in the patient.