ICD-10 Code C71.5 – Malignant neoplasm of cerebral ventricle (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code C71.5 – Malignant neoplasm of cerebral ventricle
What it is
C71.5 identifies a malignant tumor arising in the cerebral ventricle, the fluid-filled spaces within the brain. Use it when documentation specifies a primary cancer in this location.
Clinical signs
Clinical features vary; refer to documentation. Patients may present with signs of increased intracranial pressure, hydrocephalus, headache, nausea, vomiting, or neurologic deficits depending on tumor size and location.
When to use this code
Use this code when the provider documents a malignant neoplasm of a cerebral ventricle or a primary cancer centered in the ventricular system. It is appropriate for confirmed diagnoses in pathology, imaging, or operative reports when the site is clearly identified.
If the record only says “brain tumor” or gives an uncertain location, check documentation before assigning C71.5. Code the documented primary site, not a nonspecific intracranial mass.
Do not use for
Do not use this code for benign ventricular tumors, metastatic disease to the ventricle, or lesions in other brain structures. Check documentation if the site is ambiguous.
Coding tip
Verify that the cerebral ventricle is named as the primary site before coding C71.5.