Malignant neoplasm of biliary tract, unspecified

This code signifies an undifferentiated or unspecified cancerous growth originating within any part of the biliary tract. This includes the bile ducts (intrahepatic or extrahepatic), gallbladder, or ampulla of Vater, where the specific primary site cannot be determined.

Use this code when documentation confirms a malignant neoplasm of the biliary tract, but the precise anatomical origin (e.g., gallbladder, common bile duct) is not specified by the provider. This is often applicable in cases of advanced disease where the primary site is obscured or in initial diagnostic stages before definitive localization.

• Avoid using this code if a more specific primary site within the biliary tract is documented (e.g., C23 for gallbladder, C24.0 for extrahepatic bile duct).
• Always query the provider for greater specificity if possible, as a more precise code will improve data accuracy and potentially impact treatment planning.
• Sequence this code as the primary diagnosis when it represents the reason for the encounter or admission, unless another condition is clearly identified as the principal diagnosis.