Metastatic Cholangiocarcinoma Presenting With Chronic Hip Pain

Case: A 59-year-old woman presented with chronic right hip pain. Initial radiographs and CT scans were negative, but magnetic resonance imaging revealed extensive bone marrow oedema. Elevated serum CA 19-9 (3,581 kU/L) initiated further investigation, which identified an iCCA with acetabular metastasis. This case reports a rare instance of acetabular metastases from a cholangiocarcinoma. Conclusion: Since medullary bone lesions may remain occult on plain radiographs and CT, physicians must look beyond negative imaging to avoid diagnostic delays. Persistent bone pain unresponsive to conservative treatment warrants advanced imaging and systemic staging, regardless of initial findings or absence of systemic symptoms.