Obscure gastrointestinal bleeding with negative abdominal computed tomography study: The importance of enteroscopy for early diagnosis of small bowel malignancy

Small bowel tumors are rare among all gastrointestinal (GI) cancers. The most common histological subtype is adenocarcinoma. Adenocarcinoma of the small bowel is difficult to diagnose, often presents at a late stage, and has a poor prognosis. We describe a case of a patient with adenocarcinoma of the small intestine who presented to the hospital with nonspecific GI symptoms and obscure GI bleeding. An initial examination using abdominal computed tomography revealed negative findings. The patient underwent subsequent enteroscopy with capsule endoscopy and double‐balloon endoscopy, and an early‐stage jejunal adenocarcinoma was finally diagnosed.