Retroperitoneal ganglioneuroblastoma: a kaleidoscope of neuronal degeneration. A light and electron microscopic study.

The light and electron microscopic features of an unique retroperitoneal ganglioneuroblastoma in a four-year-old female are described. The unprecedented concurrence of Hirano, zebra, membranous cytoplasmic (MCB), and Pick bodies in the same population of neoplastic, sympathetic ganglion cells provides further evidence for their non-specificity. Although the pathogenesis of the membranous cytoplasmic bodies in this tumor is unclear, they ostensibly arise within endoplasmic cisterns, similar to the proposed origin of membranous cytoplasmic bodies in Tay-Sachs disease. Both the apparent continuum between argyrophilic bodies and central chromatolysis, and the incorporation of various cytoplasmic constituents within neurofilamentous proliferations reflect some of the dynamic factors involved in the formation of Pick bodies.