ICD-10 Code D43.3 – Neoplasm of uncertain behavior of cranial nerves (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code D43.3 – Neoplasm of uncertain behavior of cranial nerves
What it is
D43.3 identifies a neoplasm of uncertain behavior involving the cranial nerves. Use it when documentation describes a tumor in this location but does not clearly state whether it is benign or malignant.
Clinical signs
Clinical features vary; refer to documentation. Cranial nerve tumors may cause nerve-specific deficits such as facial weakness, sensory changes, diplopia, hearing loss, or swallowing difficulty, depending on the nerve involved.
When to use this code
Use this code when the provider documents a cranial nerve mass or neoplasm and the behavior is not specified as benign or malignant. It is also appropriate when pathology or imaging supports a neoplasm, but final behavior remains uncertain. If the record is unclear, check documentation before coding.
Do not use for
Do not use D43.3 for clearly benign or malignant cranial nerve tumors. Do not assign it when the chart only mentions symptoms, compression, or a suspected lesion without documentation of a neoplasm.
Coding tip
Confirm both the cranial nerve site and the tumor behavior in the provider record before assigning D43.3.