MountainView Hospital / Sunrise Health GME Consortium / HCA Las Vegas, NV
Nermila A. Ballmick, MD, Rylee McCracken, DO, Ann M. Wierman, MD, Hossein Akhondi, MD, Jonathan Wong, MD; MountainView Hospital / Sunrise Health GME Consortium / HCA, Las Vegas, NV
Introduction: Pancreatic cancer is the third most common cause of cancer deaths in the United States. It is considered largely incurable with a 1-year survival rate of 20% and 5-year survival rate of 7%. Meanwhile, isolated pancreatic metastases (IPM) are rare and represent about 2% of all pancreatic tumors. Determining pancreatic masses as either primary or metastatic malignancies can be difficult. Therefore, diagnostic imaging tools such as EUS-FNA with biopsy and effective sampling for immunohistochemistry (IHC) are paramount in dictating treatment options such as surgery, chemotherapy, immunotherapy, and/or radiation.
Methods: 75-year-old man with history of melanoma of the knee status-post curative wide local resection in 1997 presents with painless jaundice of two weeks. Total bilirubin was 14.1 mg/dl with direct bilirubin of 11.5. AST was elevated at 1549, ALT 1682, and ALP 3889. CEA and CA 19-9 were negative. CT of abdomen showed a pancreatic head mass with dilation of the extrahepatic, intrahepatic, cystic, and main pancreatic ducts favoring adenocarcinoma. ERCP demonstrated a large, friable ampullary mass and EUS revealed the pancreatic head mass invading into the superior mesenteric vein with tumor thrombus. FNA biopsies from the ampulla and pancreatic head were positive for S-100 and Sox-10. He was ultimately diagnosed with malignant melanoma with metastasis to the pancreatic head and biliary tract. IV interferon was started until the biliary obstruction resolved, followed by nivolumab and ipilimumab therapy. He achieved significant shrinkage in tumor size with immunotherapy and targeted radiation. Discussion: IPM is a rare phenomenon that represents 1% of metastatic melanomas. Patients with melanoma and distant metastases have a median survival of less than 1 year. Differentiating pancreatic metastases from a primary malignancy is challenging, but it is essential for optimal treatment and can influence whether surgical or non-operative management is feasible. EUS-FNA biopsy is a useful diagnostic tool that allows for effective sampling since imaging alone with CT and/or MRI cannot distinguish benign or primary pancreatic tumors from metastatic lesions. This case serves to highlight the uncommon presentation of isolated metastatic melanoma and its spread to the GI tract 22 years after initial presentation. It emphasizes the importance of proper history taking, diagnostic work-up of a pancreatic mass, and adequate tissue sampling using various imaging and procedural modalities.
(A) CT abdomen with contrast illustrating 4.5 x 2.7 x 3.3 cm pancreatic head mass as indicated by yellow circle.
(B) Application of Endoscopic Ultrasound (EUS) with fine needle aspiration (FNA) and biopsy of pancreatic head mass.
Disclosures: Nermila Ballmick indicated no relevant financial relationships. Rylee McCracken indicated no relevant financial relationships. Ann Wierman indicated no relevant financial relationships. Hossein Akhondi indicated no relevant financial relationships. Jonathan Wong indicated no relevant financial relationships.