Summary Stage 2018

See Summary Stage 2018 for the current version of the Summary Stage 2018 Manual and complete coding instructions for the Brain, CNS Other, and Intracranial Gland chapters. This is a condensed version.

See Summary Stage 2018 (SS2018) | SEER Training website for general information on Summary Stage.

Summary Stage is the most basic way of categorizing how far a cancer has spread from its point of origin. It is used by the National Cancer Institute’s (NCI) Surveillance, Epidemiology and End Results (SEER) program and the Centers for Disease Control and Prevention’s (CDC) National Program of Cancer Registrars (NPCR).

For Summary Stage, there is one general rule, “code what you know.” For example, if you know there is regional involvement, yet you have no information on the extension, code to 2 for regional involvement.

For Summary Stage, if there is no information on metastatic disease, assume there is no involvement and code Summary Stage based on the extension/size of the tumor.

For the Brain, CNS Other, and Intracranial Gland chapters, the following Summary Stage codes do not apply.

• 0: In situ. An insitu tumor in the CNS is biologically impossible
• 3 & 4: These are related to regional lymph nodes. There are no regional lymph nodes in the CNS

Note: There is no AJCC staging for Central Nervous System tumors.

Updated: September 23, 2026