Ewing Sarcoma: Rare Metastasis to the Pancreas.

Ewing sarcoma is a highly aggressive malignancy of bone or soft tissue, which may present with metastasis for 20%-25% of patients. The most common sites of metastatic lesions are the bone, bone marrow, and lungs. When metastatic lesions present within rare visceral sites, such as the pancreas, it may lead to an incorrect diagnosis of small cell neuroendocrine carcinoma. We report a case of a 37-year-old man with metastatic Ewing sarcoma involving the pancreas, confirmed by imaging, sequencing, fluorescence in situ hybridization, and histology, which was initially mistaken for small cell neuroendocrine carcinoma.