Malignant carcinoid tumor of the ileum

This code identifies a primary malignant neuroendocrine tumor originating in the ileum, a part of the small intestine. These tumors, often slow-growing, arise from enterochromaffin cells and can secrete vasoactive substances, leading to carcinoid syndrome.

Use this code for documented cases of a primary malignant carcinoid tumor specifically located in the ileum. Documentation should clearly state the malignancy and the ileal origin, often confirmed by biopsy and imaging studies.

• Ensure the documentation specifies "malignant" and not "benign" or "uncertain behavior."
• Distinguish from other neuroendocrine tumors of the small intestine, as site specificity is crucial.
• Code any associated carcinoid syndrome (e.g., E34.0) separately, as it is a manifestation, not the tumor itself.