Fig. 2.

Novel glioneuronal tumour entities. a Papillary glioneuronal tumour (PGNT). Layers of tumour cells surround vessels, forming pseudopapillary structures with b pseudopapillae covered by inner cells with hyperchromatic and outer cells with vesicular nuclei. Courtesy of Dr. Y. Nakazato. c Rosette-forming glioneuronal tumour of the fourth ventricle (RGNT). Pseudorosette with ring-like arrangement of neurocytic tumour cell nuclei around an eosinophilic neuropil core which d shows strong immunoreactivity to synaptophysin. Courtesy of Dr. J. A. Hainfellner