California Cancer Reporting System Standards Volume I: Abstracting and Coding Procedures for Hospitals
Report the stage of each case at the time of diagnosis. Consider all diagnostic and therapeutic information obtained during the first course of treatment or within four months after the date of diagnosis, whichever is earlier. This time limitation ensures that the stage recorded is based on the same information that was used to plan the patient's treatment. Exclude progression of the disease since the time of the original diagnosis.
A patient with lung cancer is staged "regional lymph nodes" by the physician on the basis of positive mediastinal lymph nodes and radiation therapy is instituted. Four weeks into the treatment course the patient develops neurological symptoms, and further work–up reveals previously unsuspected brain metastases. The treatment plan is changed to take this new manifestation into account. Since the disease has progressed since the time of original diagnosis, the stage would not be changed to distant.