Ganglioneuroma of the sacrum.

Ganglioneuromas (GNs) are benign, slow-growing, rare soft-tissue tumors that arise from the sympathetic nervous system and comprise less than 1% of all soft-tissue neoplasms. Although GNs are slow-growing, they can and will invade bone and pressure local adjacent structures by their continued growth. In a 20-year-old woman, GN produced a large presacral mass. This case illustrates the diagnostic features at various stages of growth, histopathology, and treatment of GN.