G anglioneuroma (GN) is a rare, dif fer en ti ated, be - nign and slow-growing tumor that commonly arises from sym pa thetic gan glion cells. Most GN tu mors are asymp tom atic and found in ci den tally. The pos te rior mediastinum and retroperitoneum are the most com mon sites of involvement. 1 But simutaneous extensive in - volvement of both posterior mediastinum and retro - peritoneum with out sig nif i cant symp toms is quite rare. We re port this rare case, in which tu mor in volve ment was so ex ten sive as to in clude vi tal ves sels, so that the great risk of sur gi cal re moval be came a dif fi cult chal - lenge. CASE RE PORT A 3.5-year-old mod er ately-nourished girl was quite well previously. She received plain X-ray examination film of the chest due to re spi ra tory tract in fec tion with pro duc tive cough, rhinorrhea and short ness of breath. A huge mass over the right lung ex tend ing to the left chest with pleural effusion was incidentally found. Physical examination revealed no special finding except de- creased breath sound over the right chest and mildly soft bulg ing over the right back. CT scan showed a huge tu - mor ex tend ing from the apex of the right chest to the ad - renal gland of the right retroperitoneum, space-occupying over the posterior mediastinum with intraspinal in va - sion, with out spi nal cord com pres sion. Chest sonogram showed a pos te rior mediastinal mass with fair move ment of bilateral diaphragm. Cytology of pleural effusion showed three clumps of tu mor cells. Al pha fe tal pro tein and beta-human chorionic ganadotropin (hCG) were within nor mal lim its. Ini tially, neuroblastoma was highly 370 J Chin Med Assoc 2003;66:370-374 Chia-Yau Chang 1 Yuh-Lin Hsieh 1 Giun-Yi Hung 1 Chin-Chen Pan 2 Betau Hwang 1 1 De part ment of Pe di at rics, 2 De part ment of Pa thol ogy, Tai pei Vet erans Gen eral Hos pi tal and National Yang-Ming Uni ver sity, Tai pei, Tai wan, R.O.C. Key Words ganglioneuroblastoma; ganglioneuroma; neuroblastoma; posterior mediastinum; retroperitoneum Case Report Ganglioneuroma Presenting as an Asymptomatic Huge Posterior Mediastinal and Retroperitoneal Tumor Ganglioneuroma is a rare, dif fer en ti ated, be nign and slow-growing tu mor that com - monly arises from sym pa thetic gan glion cells. Most of them are asymp tom atic and found in ci den tally. We here re port a quite rare case of si lent huge ganglioneuroma growing in both posterior mediastinum and retroperitoneum occurring in a 3.5-year-old girl. The pa tient was rel a tively well be fore and in ci den tally found to have a huge chest mass by chest X-ray film at an ep i sode of re spi ra tory tract in fec - tion. Com puted to mog ra phy showed a huge tu mor ex tend ing from bi lat eral pos te rior mediastinum to the level of the adrenal gland in the retroperitoneum. Initially, neuroblastoma was highly sus pected and 24-hour urine vanillyl mandelic acid was slightly el e vated. Cy tol ogy by bone mar row as pi ra tion re vealed no tu mor nests or clumps. Bi opsy and pa thol ogy proved it as ganglioneuroma (GN). Due to too ex ten - sive in volve ment of the tu mor and com pres sion of the vi tal ves sels, sur gi cal re moval be came dif fi cult. The fam ily of the pa tient re fused sur gery due to there be ing no sig - nif i cant symp toms. Be cause of the po ten tial for growth of unresectable GN and be - cause the com po nent of neuroblasts could not be com pletely ex cluded, the pa tient was still in dan ger ous sta tus. The only thing we can do is to keep the fam ily alert and con tinue reg u lar fol low-up. Re ceived: March 25, 2002. Ac cepted: December 13, 2002. Cor re spon dence to: Yuh-Lin Hsieh, MD, Di vi sion of Gen eral Pe di at rics, De part ment of Pe di at rics, Tai pei Vet erans Gen eral Hos pi tal, 201, Sec. 2, Shih-Pai Road, Tai pei 112, Tai wan. Fax: +886-2-2873-9019; E-mail: changtiang@ya hoo.com.tw