Which of the following is NOT a reportable case type followed by cancer registries?

The correct answer indicates that residents of foreign countries are not considered a reportable case type by cancer registries. This distinction is important because cancer registries typically focus on the local or national population from which they draw data. Their primary goal is to track and analyze cancer cases within specific geographic or jurisdictional boundaries, thereby ensuring that efforts in epidemiology, treatment effectiveness, and public health planning are relevant to the community they serve.

In the context of cancer data collection, only cases within the defined geographical area are reportable, even if a disease like cancer might occur in individuals who are foreign residents. Therefore, foreign cases fall outside the purview of most cancer registries, which are designed to monitor cancer incidence and outcomes within their jurisdiction.

For the other categories mentioned, patients aged under 100 years, those with a prior cancer history, and patients diagnosed before a certain date can be reportable based on cancer registry protocols. These groups are included because they can provide valuable data for understanding cancer trends, treatment outcomes, and long-term survivorship within the population being studied. Thus, including these populations allows registries to fulfill their mission of improving cancer care and outcomes.