**Note 1:** Clinical grade must not be blank.
**Note 2:** Assign the highest grade from the primary tumor assessed during the clinical time frame.
**Note 3:** Codes 1-4 take priority over A-D, L and H.
**Note 4:** CNS WHO classifications use a grading scheme that is a “malignancy scale” ranging across a wide variety of neoplasms rather than a strict histologic grading system that can be applied equally to all tumor types.
* Code the WHO grading system for selected tumors of the CNS as noted in the AJCC 8th edition Table 72.2 where WHO grade is not documented in the record
**Note 5:** Code 9 when
* Grade from primary site is not documented
* Clinical workup is not done (for example, cancer is an incidental finding during surgery for another condition)
* Grade checked “not applicable” on CAP Protocol (if available) and no other grade information is available
**Note 6:** If there is only one grade available and it cannot be determined if it is clinical, pathological, or after neo-adjuvant therapy, assign as a clinical grade and code unknown (9) for pathological grade, and blank for post-therapy grade.