Jejunal invasion of pheochromocytoma pathologically confirmed by endoscopic biopsy

The authors discuss a case of pheochromocytoma in a 20-year-old man referred for anemia due to gastrointestinal bleeding. Pheochromocytoma uncommonly presents with gastrointestinal bleeding, and a pathologic diagnosis is rarely made without resection of the tumor. Imaging studies demonstrated a mass on the left kidney with metastases to the liver, and high levels of catecholamines in plasma and urine were suggestive of pheochromocytoma. Endoscopic examination of the gastrointestinal tract demonstrated a mass in the proximal jejunum near the ligament of Treitz and a mass with central ulceration in the upper jejunum; biopsy confirmed the pathologic diagnosis of malignant pheochromocytoma with jejunal invasion and metastases to the liver. Gastrointestinal bleeding is one of the manifestations of pheochromocytoma. This is the first case in which endoscopic biopsy determined a pathologic diagnosis of pheochromocytoma.