Gangliogliomas are uncommon glioma of the central nervous system, generally found in the temporal lobe of young individuals with a clinical history of seizures. The tumor is a mixed tumor composed of neoplastic mature ganglion cells and neoplastic glial cells, mostly astrocytes. Although the clinicopathological correlation of this tumor is well documented, few detailed ultrastructural studies have been reported.
We studied three cases of ganglioglioma of the temporal lobe and found several unusual ultrastructural features of the neuronal cells: (1) Hirano bodies (eosinophilic rod-like structure), highly organized eosinophilic crystalloid arrays of interlocking filaments that display lattice like configuration. Homogenous electron-dense material may appear as patches permeating the fibrillar structure (Fig. 1). (2) Lafora bodies (polyglucosan bodies), round to oval non-membrane-bound inclusion composed of short branching filaments about 7-10nm in diameter and granular structures (Fig. 2). (3) Pick's bodies, perikaryonal aggregates of straight neurofilaments with or without ribosome association mixed with vesicles, myelin figures and dense bodies.