Malignant neoplasm of other and unspecified parts of biliary tract (C24) ICD-10-CM
The C24 code range covers malignant neoplasm of other and unspecified parts of biliary tract with 5 ICD-10-CM diagnosis codes. 4 of them are billable and valid for claim submission in fiscal year 2026, and the category headers group them but cannot themselves be billed.
Type 1 Excludes
A type 1 excludes note is a pure excludes note. It means "NOT CODED HERE!" An Excludes1 note indicates that the code excluded should never be used at the same time as the code above the Excludes1 note. An Excludes1 is used when two conditions cannot occur together, such as a congenital form versus an acquired form of the same condition.
- malignant neoplasm of intrahepatic bile duct C22.1
Codes in the C24 Range 5 codes · 4 billable
Clinical Terms in This Code Range
Definitions from the National Library of Medicine for conditions coded in the C24 range.
Ampulla of Vater
A dilation of the duodenal papilla that is the opening of the juncture of the COMMON BILE DUCT and the MAIN PANCREATIC DUCT, also known as the hepatopancreatic ampulla.
About the C24 Code Range
The ICD-10 codes C24 and its subcodes classify malignant neoplasms of various parts of the biliary tract, including the extrahepatic bile duct, ampulla of Vater, overlapping sites, and unspecified regions. These codes specifically identify cancers originating in these areas, essential for accurate diagnosis and treatment documentation.
The code C24.0 covers cancers of the extrahepatic bile duct and includes common terms like "primary cholangiocarcinoma of extrahepatic bile duct" or "Klatskin tumor," helping coders link these synonyms to this specific code. C24.1 refers to malignant tumors of the ampulla of Vater, capturing conditions also known as "primary carcinoma of ampulla of Vater" or "adenocarcinoma of small intestine," clarifying the site of malignancy. C24.8 is used when tumors overlap multiple biliary tract sites, encompassing terms like "carcinoma of gallbladder and extrahepatic biliary tract." When the exact location is not specified, C24.9 applies, covering general biliary tract malignancies, including references to "malignant tumor of biliary tract" or "primary adenocarcinoma of biliary tract." Understanding these codes aids medical coders in accurately classifying biliary tract cancers from a range of diagnostic terminology.
Questions About This Page
How many billable codes are in the C24 range?
Of the 5 codes in this range, 4 are billable and valid for claim submission from October 1, 2025 through September 30, 2026. Category header codes group them but cannot be reported on claims.
What does the C24 range classify?
The range classifies malignant neoplasm of other and unspecified parts of biliary tract. Each code links to its own reference page with billing status, MS-DRG grouping, coding notes, and clinical information.
Related References
Source: CMS FY 2026 ICD-10-CM Tabular List and order file, effective October 1, 2025 through September 30, 2026.
