A Resected Case of Retroperitoneal Asymptomatic Pheochromocytoma Detected in a Medical Examination

Abstract

A 50-years-old man was admitted to our hospital for examination of a retroperitoneal tumor which was found during a medical examination on abdominal ultrasonography.
Abdominal computed tomography revealed a 58mm retroperitoneal mass located in the area bounded by the dorsal duodenum, abdominal aorta, and inferior vena cava. Preoperative hormonal examinations showed elevated serum noradrenaline, although the patient was asymptomatic. MIBG scintigraphy revealed strong accumulation in the tumor. Based on preoperative examinations, we diagnosed the tumor as an asymptomatic extra-adrenal pheochromocytoma, and then performed a laparotomy. The tumor was tightly adherent to the inferior vena cava and abdominal aorta and was resected with a part of the wall of the inferior vena cava. The patientʼs blood pressure did not change when the tumor was resected.
Histological findings showed that Chromogranin A expression was observed in the tumor cells, leading to diagnosis of an extra-adrenal pheochromocytoma.
No recurrence has been observed for 24 months since the operation.