ICD-10 Code C24.9 – Malignant neoplasm of biliary tract, unspecified (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code C24.9 – Malignant neoplasm of biliary tract, unspecified
What it is
C24.9 identifies a malignant tumor in the biliary tract when the exact site is not documented. Use this code when the cancer is known to involve the bile ducts or related biliary structures, but the record does not specify a more precise location.
Clinical signs
Clinical features vary; refer to documentation. Commonly documented findings may include obstructive jaundice, right upper abdominal pain, pruritus, or imaging evidence of a biliary tract mass or stricture.
When to use this code
Use C24.9 when the provider documents a malignant neoplasm of the biliary tract without naming the exact anatomic site. It is appropriate for unspecified primary biliary cancers and for records that confirm malignancy but lack detail needed for a more specific code.
If the chart later identifies a precise bile duct or biliary site, you should code that more specific diagnosis instead. Check documentation when the term “biliary tract” is used broadly or when the site is unclear.
Do not use for
Do not use C24.9 when the tumor site is specified elsewhere in the biliary system. Do not use it for benign biliary disease, metastatic disease to the biliary tract, or nonmalignant obstruction.
Coding tip
Query the provider if the record says “biliary cancer” but does not clearly state the primary site.