Atypical Presentation of Duodenal Metastasis From Osteosarcoma: A Case Report.

Α 35-year-old male, with a history of operated osteosarcoma, was hospitalized due to a computed tomography (CT) finding at the duodenum. The patient described extreme postprandial pain at the epigastrium for seven months, accompanied by weight loss. The radiologist described a thickening at the duodenum with radiopaque lesions resembling bone, dilatation at the intrahepatic bile ducts and pancreatic duct, and dislocation of the pancreas. The CT scan and gastroscopy did not have any remarkable findings. The findings of the positron emission tomography (PET)/CT​​​​showed significant hypermetabolic activity in the extensive thickening of the duodenal wall. The results necessitated the Whipple procedure. This case highlights the need for the maintenance of high clinical suspicion, especially in patients with a history of malignancy, and the importance of diagnostic tests with greater accuracy.