Unlikely debris in the biliary tree: Metastatic prostate cancer masquerading as a Klatskin tumor

Abstract

Introduction: Prostate cancer is a common malignancy in the United States and worldwide. Most often patients present with localized disease and are asymptomatic at the time of diagnosis. Rarely, advanced disease is present at the time of initial diagnosis, usually heralded by bone pain, fatigue, or weight loss, but jaundice is typically not a presenting symptom among patients newly diagnosed with metastatic prostate cancer. Case Report: A 74-year-old male presented with painless jaundice. He had severe hyperbilirubinemia and imaging demonstrated mediastinal and abdominal lymphadenopathy in addition to biliary ductal dilation with an enhancing mass at the confluence of the left and right hepatic ducts. While the presentation and imaging were classic for a newly diagnosed Klatskin tumor, or perihilar cholangiocarcinoma, tissue biopsies from the biliary lesion and mediastinal and gastrohepatic lymph nodes were all consistent with metastatic adenocarcinoma of prostatic origin. Prostate specific antigen was elevated to 205 ng/mL. The patient underwent biliary stenting and subsequently began treatment with androgen-deprivation therapy with marked improvement in serum prostate specific antigen and resolution of hyperbilirubinemia. Conclusion: We describe a unique case of a patient who presented with painless jaundice and imaging suspicious for a Klatskin-type cholangiocarcinoma. Multiple imaging modalities and repeated biopsies were required to prove this patient actually had metastatic prostate cancer. This case highlights the importance of finalizing an accurate tissue diagnosis prior to initiating management with systemic therapies specific to disease site and biology.