2026 ICD-10-CM Diagnosis Code C24.0Malignant neoplasm of extrahepatic bile duct
ICD-10-CM Codes›C00–D49›C15-C26›C24
- Billable — Valid for Submission
- Chronic Condition
C24.0 is a billable ICD-10-CM diagnosis code for malignant neoplasm of extrahepatic bile duct. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 435 through 437. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Gastrointestinal cancers - all other types.
Code Identity
Code Classification
Approximate SynonymsGuidance
Alternate terms and clinical phrases that map to this code.
- Carcinoma common bile duct
- Carcinoma of extrahepatic bile duct
- Cholangiocarcinoma of biliary tract
- Malignant mesenchymal neoplasm of bile duct
- Malignant neoplasm of ampulla of Vater
- Malignant neoplasm of extrahepatic bile duct
- Malignant neoplasm of hepatic duct
- Malignant neoplasm of sphincter of Oddi
- Neoplasm of cystic duct
- Perihilar cholangiocarcinoma
- Primary adenocarcinoma of bile duct
- Primary adenocarcinoma of common bile duct
- Primary adenocarcinoma of cystic duct
- Primary carcinoma common bile duct
- Primary carcinoma liver and/or biliary system
- Primary carcinoma of bile duct
- Primary carcinoma of extrahepatic bile duct
- Primary cholangiocarcinoma of biliary tract
- Primary cholangiocarcinoma of extrahepatic bile duct
- Primary malignant mesenchymal neoplasm of bile duct
- Primary malignant neoplasm of common bile duct
- Primary malignant neoplasm of cystic duct
- Primary malignant neoplasm of distal bile duct
- Primary malignant neoplasm of extrahepatic bile duct
- Primary malignant neoplasm of gallbladder
- Primary malignant neoplasm of perihilar bile duct
- Primary mucinous cystic neoplasm with associated invasive carcinoma of biliary tract
- Primary mucinous cystic neoplasm with associated invasive carcinoma of cystic duct
- Primary mucinous cystic neoplasm with associated invasive carcinoma of distal bile duct
- Primary mucinous cystic neoplasm with associated invasive carcinoma of perihilar bile duct
- Primary perihilar cholangiocarcinoma
- Primary squamous cell carcinoma of gallbladder and extrahepatic biliary tract
- Squamous cell carcinoma of gallbladder and extrahepatic biliary tract
Tabular List NotesGuidance
Coding notes and annotation back-references applicable to this code.
Inclusion Terms
- Malignant neoplasm of biliary duct or passage NOS
- Malignant neoplasm of common bile duct
- Malignant neoplasm of cystic duct
- Malignant neoplasm of hepatic duct
These terms are the conditions for which that code is to be used. The terms may be synonyms of the code title, or, in the case of "other specified" codes, the terms are a list of the various conditions assigned to that code. The inclusion terms are not necessarily exhaustive. Additional terms found only in the Alphabetic Index may also be assigned to a code.
Index to Diseases and InjuriesGuidance
Alphabetical index entries that point to this code.
- Klatskin's tumor - C24.0
- Tumor - See Also: Neoplasm, unspecified behavior, by site;
- Klatskin's - C24.0
External Cause of Injuries IndexGuidance
References for this code in the External Cause of Injuries Index.
- Klatskin's tumor
- Tumor
- Klatskin's
Clinical ClassificationClinical
AHRQ’s CCSR groups this code into broader clinical categories.
Table of NeoplasmsClinical
Anatomical sites in the Table of Neoplasms that reference this code family.
| Site | Malig. Primary | Malig. Secondary | Ca in situ | Benign | Uncertain | Unspec. |
|---|---|---|---|---|---|---|
| bile or biliary (tract) › duct or passage (common) (cystic) (extrahepatic) | C24.0 | C78.89 | D01.5 | D13.5 | D37.6 | D49.0 |
| choledochal duct | C24.0 | C78.89 | D01.5 | D13.5 | D37.6 | D49.0 |
| common (bile) duct | C24.0 | C78.89 | D01.5 | D13.5 | D37.6 | D49.0 |
| cystic (bile) duct (common) | C24.0 | C78.89 | D01.5 | D13.5 | D37.6 | D49.0 |
| extrahepatic (bile) duct | C24.0 | C78.89 | D01.5 | D13.5 | D37.6 | D49.0 |
| gall duct (extrahepatic) | C24.0 | C78.89 | D01.5 | D13.5 | D37.6 | D49.0 |
| hepatic [See Also: Index to disease, by histology] › duct (bile) | C24.0 | C78.89 | D01.5 | D13.5 | D37.6 | D49.0 |
| sphincter › of Oddi | C24.0 | C78.89 | D01.5 | D13.5 | D37.6 | D49.0 |
Patient EducationClinical
Bile Duct Cancer
Your liver makes a digestive juice called bile. Your gallbladder stores it between meals. When you eat, your gallbladder pushes the bile into tubes called bile ducts. They carry the bile to your small intestine. The bile helps break down fat. It also helps the liver get rid of toxins and wastes.
The full article covers:
- What is Bile Duct Cancer (Cholangiocarcinoma)?
Read the full article at MedlinePlus
Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.
Convert C24.0 to ICD-9-CMHistory
The closest ICD-9-CM equivalents under the General Equivalence Mappings.
Code HistoryHistory
Questions About C24.0Overview
Is C24.0 a billable code?
Yes. This is a billable ICD-10-CM code, specific enough to report malignant neoplasm of extrahepatic bile duct on HIPAA-covered claims from October 1, 2025 through September 30, 2026.
What MS-DRG does C24.0 group to?
When malignant neoplasm of extrahepatic bile duct is the principal diagnosis on an inpatient stay, it groups to MS-DRG 435, 436, 437, with relative weights from 0.8533 to 1.8367 depending on complications. Higher weights mean higher Medicare reimbursement.
What is the ICD-9 equivalent of C24.0?
Under the General Equivalence Mappings, malignant neoplasm of extrahepatic bile duct converts to ICD-9-CM 156.1 (mal neo extrahepat ducts). The mapping is a direct match.
Footnotes
[1] Chronic - a chronic condition code indicates a condition lasting 12 months or longer and its effect on the patient based on one or both of the following criteria:
- The condition results in the need for ongoing intervention with medical products,treatment, services, and special equipment
- The condition places limitations on self-care, independent living, and social interactions.
