Adenocarcinoma of the Small Intestine in a Young Adult Diagnosed by Double-balloon Enteroscopy

A 29-year-old man presented with a 3-month history of abdominal pain and appetite loss. Superficial lymph node adenopathy was noted. Systemic computed tomography showed multiple liver and lung metastases, as well as ascites. No abnormalities were found on upper gastrointestinal endoscopy and colonoscopy; therefore, double-balloon enteroscopy was performed. A stenosis with reddish and edematous mucosal changes from the third part of the duodenum to the upper jejunum was noted; on histopathology of the biopsy specimens, adenocarcinoma was diagnosed. Thus, the patient had advanced small intestinal cancer with carcinomatous peritonitis and liver metastases. Although the patient was given chemotherapy with cisplatin and 5-fluorouracil, he died 2 months after commencing treatment. Primary small intestinal carcinoma is a rare malignancy; most cases cannot be detected on routine gastrointestinal endoscopy due to their location. Our experience suggests that double-balloon enteroscopy is useful for diagnosing small intestinal adenocarcinoma