Malignant biliary tract obstruction (MBTO) is most commonly associated with primary hepatobiliary and pancreatic malignancies. Here, we present a rare case of a 65-year-old female who developed obstructive jaundice, which initially raised suspicion for hepatobiliary carcinoma. Cross-sectional imaging, including computed tomography and magnetic resonance imaging, revealed hepatic lesions, and endoscopic retrograde cholangiopancreatography demonstrated a malignant biliary stricture. Histopathological analysis of a liver biopsy unexpectedly confirmed metastatic urothelial carcinoma (UC). Further evaluation with cystoscopy, prompted despite the absence of urinary symptoms, identified a small bladder mass, which was biopsy-proven as the primary UC. UC typically metastasizes to lymph nodes, lungs, or bones, and isolated liver involvement causing MBTO is exceptionally uncommon. This case underscores the importance of maintaining a broad differential diagnosis in patients with malignant biliary obstruction, as atypical metastatic patterns can mimic more common hepatobiliary cancers and delay appropriate management.

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