Although liver metastasis commonly occurs in patients with colorectal cancer (CRC), it is infrequent that it presents several years after curative resection for early-stage disease. Even more unusual is development of intrabiliary growth type metastasis rather than parenchymal metastasis. When this occurs, it can be mistaken for cholangiocarcinoma. We present a case in a patient with history of pT1N0M0 CRC treated with sigmoidectomy 7 years previously who presented with abdominal pain and MRI revealing left hepatic ductal dilation with no accompanying mass. With a recent normal colonoscopy and carcinoembryonic antigen, he was diagnosed with cholangiocarcinoma. Anatomic hepatic resection was performed, and final pathology with immunohistochemistry revealed staining consistent with CRC metastasis rather than cholangiocarcinoma. Intrabiliary growth type metastasis is a rare occurrence, which leads to its misdiagnosis. Patients with an intrabiliary tumor and a history of CRC should have immunohistochemistry to confirm the diagnosis to ensure appropriate adjuvant treatment and counseling.
Keywords: cholangiocarcinoma; colorectal cancer; hepatectomy; intrabiliary growth; metastasis.