Malignant carcinoid tumor of the hindgut, unspecified

This code describes a malignant neuroendocrine tumor originating in the hindgut (distal transverse colon, descending colon, sigmoid colon, rectum, and anal canal) where the specific primary site within the hindgut is not documented. These tumors are characterized by their ability to produce and secrete various hormones, leading to carcinoid syndrome in some cases.

Use this code when documentation confirms a malignant carcinoid tumor of the hindgut, but the precise anatomical location (e.g., rectum vs. sigmoid colon) is not specified. This code is appropriate when the pathology report or clinical notes indicate a hindgut origin without further detail.

• Ensure "malignant" is explicitly stated; benign carcinoid tumors are coded differently.
• Avoid this code if a more specific hindgut location (e.g., rectum, sigmoid colon) is documented; use the appropriate site-specific code.
• Consider sequencing this code as the primary diagnosis when it is the reason for the encounter, followed by codes for any associated carcinoid syndrome or metastatic disease.