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SEER Inquiry System - Report
Produced: 05/26/2026 6:14 PM
Question 20220041
Inquiry Details
References:
#1: Subject matter expert
#2: ICD-O-3
Question:
Primary Site/Histology--Intrahepatic Duct: How are primary site and histology coded for cholangiocarcinoma cases when the pathology only shows a liver tumor and other involvement. See Discussion.
Discussion:
A common scenario is a patient has a positive CT of the abdomen/pelvis for liver mass only. Biopsy of the liver mass is positive for cholangiocarcinoma. The physician is also calling the liver tumor the primary site with histology of cholangiocarcinoma. There is no evidence of intrahepatic bile duct (C221) or gallbladder (C240) involvement which are sites specific to this histology. The hematology/oncology consult stages this as Stage IIIA, T3N0M0 intrahepatic cholangiocarcinoma. Can we code cholangiocarcinoma with site code C220 (liver) or should we assume that C221 (intrahepatic bile ducts) would be a better code to reflect this histology?
Answer:
Assign C221 (intrahepatic bile duct) as the primary site for cholangiocarcinoma (8160/3). Our expert GI pathologist confirms that even when intrahepatic bile ducts are not specifically mentioned, intrahepatic cholangiocarcinoma originates in the intrahepatic bile ducts.
