Secondary malignant neoplasm of unsp part of nervous system

This code signifies the presence of a metastatic cancer that has spread to an unspecified location within the nervous system (e.g., brain, spinal cord, cranial nerves, peripheral nerves). It indicates that the nervous system tumor is secondary to a primary malignancy elsewhere in the body.

Use this code when documentation confirms a metastatic malignant neoplasm to the nervous system, but the specific site within the nervous system is not documented or is unknown. This code is appropriate when the primary site of the cancer is known or being treated, and the nervous system involvement is a secondary manifestation.

• Always sequence the primary malignant neoplasm first, followed by this code.
• Avoid using this code if a more specific site within the nervous system (e.g., C79.31 for secondary malignant neoplasm of brain) is documented.
• Ensure documentation clearly states "metastatic to nervous system" or "secondary malignant neoplasm of nervous system" without further anatomical specificity.