Undifferentiated pleomorphic sarcoma (UPS), previously known as malignant fibrous histiocytoma, is the most common type of soft tissue sarcoma. Commonly seen in the extremities, UPS is an uncommon primary tumor of the GI tract. We report a case of an elderly female with a known renal neoplasm who incidentally was found to have a malignant lesion in the epigastrium. Given exophytic character abutting the stomach and pancreas, the mass initially thought to represent a gastrointestinal stromal tumor arising from the stomach. Biopsy of the mass showed atypical and pleomorphic malignant cells of unknown differentiation and was nonreactive with various immunohistochemical markers including both stromal and epithelial cell lines. A poorly differentiated sarcomatoid neoplasm of the pancreas was diagnosed.
Published on: May 18, 2021
Citation: Ehrhart M, Hanson JA, Boehler C, Runde RE, Thompson WM. 2021. Pancreatic Undifferentiated Pleomorphic Sarcoma Mimicking a Gastric Gastrointestinal Stromal Tumor. J Med Imaging Case Rep 5(1): 22-24.