S1621 Pancreatic Metastasis From Synovial Sarcoma

Abstract

Introduction: Synovial sarcoma metastasizes in approximately 50% of cases, and common metastatic sites are the lung and bone. Metastasis to the pancreas is rare and only 6 cases have been reported. We report another case of pancreatic metastasis from synovial sarcoma. Case Description/Methods: A 49-year-old female with a past medical history of synovial sarcoma of the left upper thigh presented with a 1-month history of abdominal pain. She was diagnosed with synovial sarcoma one year ago and had stable disease after receiving 6 cycles of chemotherapy as well as radiation therapy. Her pain was epigastric, dull, constant, and worse after food intake. A CT of her abdomen with contrast showed 2x2 cm and 2.2x1.5cm heterogeneously enhancing lesions in the body and tail of the pancreas. An EGD with biopsy was positive for Helicobacter pylori. An EUS was performed and the celiac axis was free of lymphadenopathy. A fine needle biopsy of the pancreatic lesions was performed with pathology showing poorly differentiated metastatic synovial sarcoma. Chemotherapy was initiated with gemcitabine and docetaxel. However, she continued to have disease progression after 6 months of treatment, and eventually enrolled under hospice care. Discussion: Metastatic pancreatic cancer accounts for less than 2% of all pancreatic malignancies. The most common primary tumors being renal cell carcinoma, melanoma, and lung cancer. Metastatic sarcomas present a diagnostic and therapeutic challenge due to their rarity. Our case is only the 7th reported synovial sarcoma with metastasis to the pancreas. Half of these cases are asymptomatic and the other half have symptoms like abdominal pain. A review of the available cases showed prolonged survival after surgical resection +/- chemotherapy. Unfortunately, our patient was not a candidate for resection due to the extent of her metastasis. Instead, palliative care services were offered to our patient.Figure 1.: CT Abdomen showing heterogeneously enhancing mass on the pancreas (red arrow).