2016 Volume 55 Issue 4 Pages 274-279
Background : Papillary glioneuronal tumors (PGNTs) are characterized by a pseudopapillary architecture associated with areas of compact neuronal elements in different states of maturation. In the updated 2007 WHO classification of tumors of the central nervous system, PGNTs are identified as a distinct entity, typically corresponding to WHO grade I CNS tumors. Until date, there are no reports of the cytological characteristics of PGNTs.
Case : A 32-year-old woman was admitted to Fukuoka University Hospital with a right temporal lobe tumor. Total resection of the tumor was performed via a right temporo-parietal craniotomy. Intraoperative cytology showed perivascular astrocytes with round to oval nuclei and short cell processes, as well as larger ganglion-like cells and neuronal cells. On the basis of these cytological features, possible glioneuronal tumor was suspected. Postoperative histological examination of the resected specimen revealed a complex pseudopapillary architecture of the tumor. Thickened hyalinized vascular walls were lined by a single layer of small, regular astrocytes, accompanied by proliferating neuronal cells with round nuclei and clear cytoplasm arranged in sheets between the pseudopapillae, which led to the diagnosis of PGNT.
Conclusion : In retrospect, the intraoperative cytological findings were sufficient to make the diagnosis of PGNT. This was an important educational case, demonstrating that even rare glioneuronal tumors can be diagnosed during operation using appropriate cytological techniques.
