Claire Pedroso, MD1, Sara West, DO2, Harshit S. Khara, MD, FACG1; 1Geisinger Medical Center, Danville, PA; 2Geisinger Health System, Danville, PA
Introduction: Sarcoma of the pancreas is a rare and aggressive nonepithelial tumor in the pancreas with an incidence of < 0.1% of all pancreatic malignancies. It is histologically composed of pleomorphic spindle cells with large atypical nuclei. Patients may present with abdominal pain, nausea, vomiting, jaundice or large abdominal mass. Here we present a rare case of metastatic pancreatic sarcoma with mediastinal mass masquerading as acute necrotic collection.
Methods: A 66-year-old male presented to ED with progressive back pain and underwent a non-contrast CT abdomen and pelvis revealing pancreatitis with developing pseudocyst versus an area of necrosis. Blood work showed normal liver function tests (alk phos 106 U/L, ALT 27 U/L, AST 27 U/L, T Bili 1.2 mg/dL) and mildly elevated lipase (85 U/L). With concern for pancreatitis with acute necrotic collection or malignancy, patient underwent a follow up CT chest, abdomen and pelvis with IV and PO contrast revealing a large 58 mm mediastinal mass and a 40 mm pancreatic body mass (Figure 1) with suspected metastatic lesions to the lungs, liver and kidney. Endoscopic ultrasound (EUS) elucidated a mixed solid and cystic hypoechoic mass in the pancreatic body measuring 49 mm x 44 mm (Figure 2) and an irregular mediastinal mixed solid and cystic hypoechoic mass measuring 42 mm x 44 mm (Figure 3). EUS-guided fine needle biopsy (EUS-FNB) of the pancreatic and mediastinal mass revealed high-grade sarcoma with similar immunophenotype for both lesions. It was immunohistochemically positive for vimentin, CD56, SATB2, antitrypsin. Patient was seen by Oncology and planned to start chemotherapy with doxorubicin. Discussion: Pancreatitis complicated by a pseudocyst or acute necrotic collection is not an uncommon finding in patients presenting with pancreatitis however our case demonstrates the importance of ruling out malignancy on these cases. Pancreatic sarcoma appears on imaging as a heterogenous well circumscribed lesion with peripheral enhancement, components of necrosis and hemorrhage and usually a normal caliber pancreatic duct. EUS-FNB led to the definitive diagnosis of a rare presentation of pancreatic sarcoma.
Figure 1. CT chest, abdomen and pelvis with IV and PO contrast revealing 40 mm x 37 mm x 38 mm hypoenhancing pancreatic mass.
Figure 2. EUS revealing a mixed solid and cystic hypoechoic mass in the pancreatic body measuring 49 mm x 44 mm.
Figure 3. EUS revealing a heterogenous hypoechoic mass in the mediastinum measuring 44 mm x 42 mm.
Disclosures: Claire Pedroso indicated no relevant financial relationships. Sara West indicated no relevant financial relationships. Harshit Khara indicated no relevant financial relationships.