For which purpose is the "Summary Stage 2018" used?

The "Summary Stage 2018" is utilized primarily for determining the stage of cancer at the time of diagnosis. This staging system helps classify the extent of cancer's spread through standard categories, such as local, regional, or distant. This information is crucial for understanding prognosis, treatment decisions, and the evaluation of treatment outcomes, which can influence overall patient management. Accurate staging can also aid in cancer research and statistical reporting, providing essential data for public health initiatives.

While other options mention relevant aspects of patient management or data registration, they do not focus specifically on the role of "Summary Stage 2018" in establishing cancer stage at diagnosis, which is its primary intention.