Rosette-forming glioneuronal tumors (RGNTs) with FGFR1 tyrosine kinase domain internal tandem duplication (FGFR1 ITD) is exceedingly rare, with only a few cases reported in the literature. Hereby we present a case of a tumor with RGNT morphology occurring in area of septum pellucidum of 43-year-old male. The tumor showed FGFR1 ITD, no PIK3CA, PIK3R1 or NF1 alterations and inconclusive methylation profile with match for class of "low-grade glial/glioneuronal/neuroepithelial tumors". No areas characteristic of dysembryoplastic neuroepithelial tumor were identified. A brief review of literature on discrepancies between morphological diagnosis of RGNT and molecular profile of the entity is provided.

Bioptical Laboratory Ltd Pilsen Czech Republic

Cytopathos Ltd Bratislava Slovak Republic

Department of Neurosurgery and Neurooncology 1st Medical Faculty Charles University Military University Hospital Prague Prague Czech Republic

Department of Pathology Charles University 1st Faculty of Medicine and General University Hospital Prague Prague Czech Republic

Department of Pathology Military University Hospital Prague Prague Czech Republic

The Fingerland Department of Pathology Charles University Faculty of Medicine in Hradec Králové and University Hospital Hradec Králové Hradec Kralove Czech Republic

The Sikl Department of Pathology Charles University Faculty of Medicine in Pilsen Pilsen Czech Republic

Zobrazit více v PubMed

Appay R, Bielle F, Sievers P et al. Rosette‐forming glioneuronal tumours are midline, FGFR1‐mutated tumours. Neuropathol Appl Neurobiol 2022; 48: e12813.

Sievers P, Appay R, Schrimpf D et al. Rosette‐forming glioneuronal tumors share a distinct DNA methylation profile and mutations in FGFR1, with recurrent co‐mutation of PIK3CA and NF1. Acta Neuropathol 2019; 138: 497–504.

Komori T, Scheithauer BW, Hirose T. A rosette‐forming glioneuronal tumor of the fourth ventricle: Infratentorial form of dysembryoplastic neuroepithelial tumor? Am J Surg Pathol 2002; 26: 582–591.

Lucas CG, Gupta R, Doo P et al. Comprehensive analysis of diverse low‐grade neuroepithelial tumors with FGFR1 alterations reveals a distinct molecular signature of rosette‐forming glioneuronal tumor. Acta Neuropathol Commun 2020; 8: 151.

Rivera B, Gayden T, Carrot‐Zhang J et al. Germline and somatic FGFR1 abnormalities in dysembryoplastic neuroepithelial tumors. Acta Neuropathol 2016; 131: 847–863.

Ryall S, Zapotocky M, Fukuoka K et al. Integrated molecular and clinical analysis of 1,000 pediatric low‐grade gliomas. Cancer Cell 2020; 37: 569–583.

Matsumura N, Nobusawa S, Ito J et al. Multiplex ligation‐dependent probe amplification analysis is useful for detecting a copy number gain of the FGFR1 tyrosine kinase domain in dysembryoplastic neuroepithelial tumors. J Neuro‐Oncol 2019; 143: 27–33.

Bale TA. FGFR‐ gene family alterations in low‐grade neuroepithelial tumors. Acta Neuropathol Commun 2020; 8: 21.

Lucas CG, Villanueva‐Meyer JE, Whipple N et al. Myxoid glioneuronal tumor, PDGFRA p.K385‐mutant: Clinical, radiologic, and histopathologic features. Brain Pathol 2020; 30: 479–494.

Thom M, Toma A, An S et al. One hundred and one dysembryoplastic neuroepithelial tumors: An adult epilepsy series with immunohistochemical, molecular genetic, and clinical correlations and a review of the literature. J Neuropathol Exp Neurol 2011; 70: 859–878.

Chen SY, Wang W, Wang LM et al. Glioneuronal tumours with features of rosette‐forming glioneuronal tumours of the fourth ventricle and dysembryoplastic neuroepithelial tumours: A report of three cases. Histopathology 2016; 68: 378–387.

Matyja E, Grajkowska W, Kunert P, Marchel A. A peculiar histopathological form of dysembryoplastic neuroepithelial tumor with separated pilocytic astrocytoma and rosette‐forming glioneuronal tumor components. Neuropathology 2014; 34: 491–498.

Sumitomo N, Ishiyama A, Shibuya M et al. Intractable epilepsy due to a rosette‐forming glioneuronal tumor with a dysembryoplastic neuroepithelial background. Neuropathology 2018; 38: 300–304.

Uchiyama T, Gomi A, Nobusawa S, Fukushima N, Matsubara D, Kawai K. A case of a rosette‐forming glioneuronal tumor with clinicopathological features of a dysembryoplastic neuroepithelial tumor and fibroblast growth factor receptor 1 internal tandem duplication. Brain Tumor Pathol 2021; 38: 250–256.

Louis DN, Wesseling P, Paulus W et al. cIMPACT‐NOW update 1: Not otherwise specified (NOS) and not elsewhere classified (NEC). Acta Neuropathol 2018; 135: 481–484.

Halfpenny A, Ferris SP, Grafe M et al. A case of recurrent epilepsy‐associated rosette‐forming glioneuronal tumor with anaplastic transformation in the absence of therapy. Neuropathology 2019; 39: 389–393.