Composite paraganglioma with neuroblastoma in retrohepatic retroperitoneum mimicking hepatocellular carcinoma

Abstract

Introduction: Paraganglioma is more common in the head and neck region than in the retroperitoneum. Neuroblastoma is one of the derived from the embryonal sympathetic nervous system usually developed in children. Composite paraganglioma with neuroblastoma(CPN) consists of a neuroendocrine component mixed with a neural component, and has been reported occasionally in the children, but extremely rarely in the adult. Methods: A 62-year-old man visited complaining right upper abdominal pain. Abdominal CT and MRI demonstrated 11x11x16 cm sized multiseptated cystic mass that contained hemorrhagic fluid in right hepatic lobe. All routine laboratory finding with tumor markers were within normal range. The elective operation was planned under the impression of hepatocellular carcinoma in right lobe of liver with questionable retroperitoneal invasion. In operation finding, there was about 20x15cm sized large mass was detected in the area between posterior portion of right hepatic lobe and retrohepatic retroperitoneum with invasion of right adrenal gland. Right hepatectomy and right adrenalectomy with resection of retroperitoneal tissue was performed. Results: The tumor was well marginated and demarcated from the liver, and was composed with both cystic and solid component. Pathological result of cystic lesion was paraganlglioma with CD56(+), synaptophysin(+) and Ki-67(+, 2-3%). On the other hand, the res solid component was anaplastic neuroblastoma with CD56(+), synaptophysin(-), Ki-67(+, 10-15%). The final pathological diagnosis was confirmed by CPN in retroperitoneum. Conclusions: CPN of the retropeitoneum developed in the adult extremely rare. Here in, we report a case of retroperitoneal CPN mimicking hepatocellular carcinoma developed in the adult.