C71.5 vs C71.7
C71.5 and C71.7 can never be reported together. ICD-10-CM declares them mutually exclusive with an Excludes1 note, meaning the two conditions cannot occur in the same patient — so exactly one of them is correct for any given encounter.
The official note, declared on C71.5
malignant neoplasm of fourth cerebral ventricle (C71.7)
C71.5
Malignant neoplasm of cerebral ventricle
Billable
- Chapter 2
- Neoplasms
- Section
- C69-C72
Indexed under
- Papilloma › choroid plexus › anaplastic
- Papilloma › choroid plexus › malignant
C71.7
Malignant neoplasm of brain stem
Billable
- Chapter 2
- Neoplasms
- Section
- C69-C72
Use when the record says
- Malignant neoplasm of fourth cerebral ventricle
- Infratentorial malignant neoplasm NOS
Excludes1 is not always absolute: where two conditions covered by the note are genuinely unrelated, CMS guidance permits reporting both. Document the reasoning rather than assuming it. More on Excludes1 vs Excludes2 · FY2027