Malignant neoplasm of cauda equina

This code signifies a primary cancerous tumor originating in the cauda equina, which is the bundle of spinal nerves and nerve roots extending from the end of the spinal cord. These neoplasms can compress the nerves, leading to neurological deficits in the lower extremities and pelvic organs.

Assign this code when documentation clearly indicates a primary malignant neoplasm affecting the cauda equina. This diagnosis is typically supported by imaging studies (e.g., MRI) and often confirmed by biopsy. Use this code for the initial diagnosis and subsequent encounters for treatment of the primary malignancy.

• Distinguish from secondary metastatic lesions to the cauda equina, which would be coded differently.
• Always sequence this code as the primary diagnosis when it is the reason for the encounter.
• Ensure documentation specifies "malignant" and "primary" to support this specific code.