Neoplasm of uncertain behavior of cerebral meninges

This code signifies a brain tumor originating from the meninges (the membranes surrounding the brain) where the pathologist cannot definitively classify it as benign or malignant based on microscopic examination. It indicates that the biological behavior of the neoplasm is currently indeterminate.

Apply this code when pathology reports describe a meningeal tumor as "atypical," "borderline," or "of uncertain malignant potential." Documentation must explicitly state the neoplasm's uncertain behavior and its cerebral meningeal origin.

• Do not use this code if the pathology report definitively classifies the meningeal tumor as benign (e.g., meningioma) or malignant (e.g., anaplastic meningioma).
• Ensure the documentation specifies "cerebral meninges" to differentiate from spinal meninges (D42.1).
• Always sequence this code as the primary diagnosis when it is the reason for the encounter, unless another condition is clearly the principal diagnosis.