Case report: when colon cancer hides inside the bile ducts
Spread confined to the bile ducts in an 82-year-old man looked like a different cancer.
Colon cancer that travels into the bile ducts while sparing the liver itself is very unusual, and it can fool the doctors looking at the scans.
A case report in The Ulutas Medical Journal describes an 82-year-old man on chemotherapy after colon surgery whose tumour markers began to rise. Imaging showed tissue inside the bile ducts and multiple narrowings, yet no mass in the liver.
Three explanations were on the table: a new bile duct cancer, duct damage from chemotherapy, or metastasis. Bile cytology found no cancer cells, but a CT-guided biopsy showed a staining profile (CK7-negative, CK20- and CDX-2-positive) that made metastasis the leading suspect.
His condition deteriorated, and he died about a month later of a worsening biliary infection.
The authors want clinicians to keep this rare pattern in mind, because it can pass for primary bile duct cancer or chemotherapy injury.
Caveat: a single case cannot say how common this is or how best to treat it.
Source: Po-Yuan Chen et al. Intrabiliary Metastasis of Colon Cancer Mimicking Cholangiocarcinoma and Chemotherapy-Induced Sclerosing Cholangitis: A Case Report. Ulutas Med J 2022. doi:10.5455/umj.20220222072137.
Image: Figure 3 of the article, CC BY-NC 4.0.
