The patient had an intracranial biopsy on July 1, 2004, and the tumor pathology was WHO grade I schwannoma.
Primary site: C72.5 cranial nerves NOS
Histology: 9560/09 schwannoma NOS
Non-malignant intracranial tumors are reportable for cases diagnosed January 1, 2004 and later. Intracranial schwannoma with no specific site identified is coded to cranial nerves NOS. The reference is ICD-O-3, page 24, Rule A - "If the diagnosis does not specify the tissue of origin, code the appropriate tissues suggested in the alphabetic index for each ill-defined site in preference to the 'NOS' category." Schwannoma arises from the nerve sheath and consists of Schwann cells in a collagenous matrix.
The grade for all benign and borderline tumors is 9 (unknown, not applicable). The reference is ICD-O-3, page 30, Rule G, paragraph 1 - "Only malignant tumors are graded." WHO grade is not coded as part of the histology, but it is coded in a collaborative stage site-specific factor.