Papillary glioneuronal tumour: a review of the literature with two illustrative cases.

We report two cases of papillary glioneuronal tumour (PGNT). One was located in the supratentorial parenchyma and the other was intraventricular. Both patients underwent gross total resection of their tumour and have returned to normal lifestyle. Papillary glioneuronal tumor is a recently described rare cerebral neoplasm. Recently classified by the World Health Organization in 2007 as a Grade I neuronal-glial tumour, these tumours are infrequent lesions that can be challenging to the practising pathologist. Patients commonly present with headaches or seizures, but may be asymptomatic with the mass discovered incidentally. The characteristic radiological, histological and immunohistochemical features are discussed. Surgical excision has been curative in most of the cases with only a handful of cases of recurrence reported. The increasing number of reports in the literature shows how PGNT forms a good example of a newly diagnosed tumour category in evolution. New classifications and re-classifications of broad categories of brain tumours will hopefully lead to a narrower diagnostic, prognostic and therapeutic profile. The even rarer presence of atypia calls for longer follow-up to help elucidate further its biological behaviour.