Malignant neoplasm of cranial nerves

This code signifies the presence of a cancerous tumor originating from or involving any of the twelve pairs of cranial nerves. These nerves control various sensory and motor functions of the head and neck, and a malignant neoplasm can impair these functions. The specific symptoms depend on the cranial nerve(s) affected.

Use this code when documentation explicitly states a malignant neoplasm of a cranial nerve, such as an optic nerve glioma or an acoustic neuroma (if malignant). This diagnosis is typically confirmed through imaging studies (MRI, CT) and often biopsy. The physician's final diagnosis must clearly indicate malignancy.

• Ensure the documentation specifies "malignant" for the cranial nerve tumor; otherwise, consider benign neoplasm codes.
• If the primary site of the malignancy is elsewhere and has metastasized to a cranial nerve, code the primary malignancy first, followed by a secondary malignancy code.
• Be careful not to confuse with benign tumors of cranial nerves (e.g., 225.1 for benign neoplasm of cranial nerves).