Abstract
Small bowel adenocarcinoma (SBA) is an uncommon gastrointestinal malignancy, with the duodenum being the most commonly affected site. This report describes a 33-year-old woman who initially presented with abdominal pain and vomiting. Initial imaging revealed abnormalities of the proximal jejunum. Endoscopic evaluation initially revealed celiac disease (CD); however, with disease progression, the patient developed bowel obstruction that led to surgical intervention with an open duodenal biopsy. The open duodenal biopsy confirmed the presence of duodenal adenocarcinoma (DA). This case demonstrates the diagnostic complexity of DA in the presence of concurrent CD due to overlapping presentations. Physicians must maintain a high suspicion of DA in the setting of progressive and difficult-to-treat CD, as early diagnosis and management of DA can significantly improve patient outcomes.