Analysis of a Novel Translocation, T(9;17)(Q31;Q24), in Rosette-Forming Glioneuronal Tumors

Abstract

ABSTRACT Aim: Papillary glioneuronal tumor (PGNT) and rosette-forming glioneuronal tumor (RGNT) were recently established unusual glioneuronal phenotypes and were categorized as a novel tumor entity in the 2007 World Health Organization classification. The molecular background of these glioneuronal tumors remains poorly understood due to a paucity of reports. Recently, the SLC44A1-PRKCA fusion has been identified in 3 cases of PGNT. Methods: The aim of this study was to confirm it in our 3 cases of PGNT and analyze the presence of specific fusion in 2 cases of RGNT, using fluorescence in situ hybridization. Results: Two out of three PGNT cases showed one adjacent red-green signal pair representing the rearrangement on chromosome 9 and 17, but not a complete fused yellow signal. Normal signal pattern was observed in the other PGNT case. Neither of two RGNT cases revealed adjacent red-green signal pair or yellow signal. Conclusions: The SLC44A1-PRKCA fusion is a characteristic alteration in PGNT but not in RGNT, and is suggested as a potential biomarker of PGNT. One adjacent red-green signal pair observed in the PGNTs may imply the presence of different breakpoints from those previously reported in the 9q31 and 17q24 genes. Disclosure: All authors have declared no conflicts of interest.