EOD Primary Tumor
**Note 1:** The tentorium cerebelli is an extension of the dura mater that separates the cerebellum from the inferior portion of the occipital lobes. The location of the tumor above or below the tentorium can help in determining the type of tumor; also most adult brain tumors are supratentorial, and most pediatric brain tumors are infratentorial. In the following list, note that ICD-O-3 codes C71.0 and C71.9 include both supratentorial and infratentorial subsites.
**Infratentorial sites by ICD-O-3 codes**
C710: Hypothalamus, pallium, thalamus
**Supratentorial sites by ICD-O-3 codes**
C710, except hypothalamus, pallium, thalamus
C718: Corpus callosum, tapetum
C719: Anterior cranial fossa, middle cranial fossa, suprasellar
**Note 2:** Discontiguous spread, including circulating cells in cerebrospinal fluid (CSF), is coded in EOD Mets.
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