Secondary malignant neoplasm of large intestine and rectum

This code signifies the presence of a malignant tumor in the large intestine or rectum that originated from a primary cancer elsewhere in the body and has metastasized to these sites. It indicates a secondary, not primary, cancerous growth within the colorectal region.

Apply this code when documentation clearly states a metastatic malignancy to the large intestine or rectum. This typically occurs in patients with a known history of a primary cancer (e.g., lung, breast, stomach) that has spread. Pathology reports confirming metastatic carcinoma in these anatomical sites support its use.

• Always sequence the primary malignant neoplasm first, followed by this code for the secondary site.
• Distinguish carefully between primary (C18.-, C19, C20) and secondary (C78.5) colorectal malignancies based on documentation.
• Ensure the medical record specifies "metastatic" or "secondary" to the large intestine or rectum, not just "tumor" or "lesion."