Diffuse leptomeningeal glioneuronal tumor (DLGNT) is a rare, primary CNS tumor, classified as distinct entity in 2016Johnson, D.R.; Guerin, J.B.; Giannini, C.; Morris, J.M.; Eckel, L.J.; Kaufmann, T.J. 2016 Updates to the WHO Brain Tumor Classification System: What the Radiologist Needs to Know. Radiographics 2017, 37, 2164–2180 and described as diffuse oligodendroglial-like leptomeningeal tumor of children in the 2016 classification of CNS neoplasms by the WHO.,Louis DN, Perry A, Reifenberger G, von Deimling A, Figarella-Branger D, Cavenee WK, Ohgaki H, Wiestler OD, Kleihues P, Ellison DW (2016) The 2016 World Health Organization classification of tumors of the central nervous system: a summary. Acta Neuropathol 131:803–820. https://doi.org/10.1007/s00401-016-1545-1 Typically, it's considered juvenile tumorsRodriguez FJ, Perry A, Rosenblum MK, Krawitz S, Cohen KJ, Lin D, Mosier S, Lin MT, Eberhart CG, Burger PC (2012) Disseminated oligodendroglial-like leptomeningeal tumor of childhood: a distinctive clinicopathologic entity. Acta Neuropathol 124:627–641. doi:10.1007/s00401-012-1037-x but can occur in adults,Chiang JCH, Harreld JH, Orr BA, Sharma S, Ismail A, Segura AD, Ellison DW (2017) Low-grade spinal glioneuronal tumors with BRAF gene fusion and 1p deletion but without leptomeningeal dissemination. Acta Neuropathol 134:159–162. https://doi.org/10.1007/s00401-017-1728-4 the average age of diagnosis is five years. It's characterised by wide leptomeningeal spreadAgamanolis DP, Katsetos CD, Klonk CJ, Bartkowski HM, Ganapathy S, Staugaitis SM, Kuerbitz SJ, Patton DF, Talaizadeh A, Cohen BH (2012) An unusual form of superficially disseminated glioma in children: report of 3 cases. J Child Neurol 27:727–733 with male predominance,Lyle, M.R.; Dolia, J.N.; Fratkin, J.; Nichols, T.A.; Herrington, B.L. Newly Identified Characteristics and Suggestions for Diagnosis and Treatment of Diffuse Leptomeningeal Glioneuronal/Neuroepithelial Tumors: A Case Report and Review of the Literature. Child Neurol. Open 2015, 2, 2329048X14567531 like histopathology of neurocytoma,Psarros TG, Swift D, Mulne AF et al (2005) Neurocytoma-like neoplasm of the thoracic spine in a 15-month-old child presenting with diffuse leptomeningeal dissemination and communicating hydrocephalus. Case report. J Neurosurg 103:184–190 oligodendrocyte-like cytopathology,Korein J, Feigin I, Shapiro MF (1957) Oligodendrogliomatosis with intracranial hypertension. Neurology 7:589–594 bland appearance, and severe clinical behaviour.Mathews MS, Pare LS, Kuo JV, Kim RC (2009) Primary leptomeningeal oligodendrogliomatosis. J Neurooncol 94:275–278Chen R, Macdonald DR, Ramsay DA (1995) Primary diffuse leptomeningeal oligodendroglioma. Case report. J Neurosurgery 83:724–728 Children's basal cisterns and inter-hemispheric fissures are typically involved in plaque like subarachnoid tumors. A common related intraparenchymal lesion is a spinal lesion.Gardiman MP, Fassan M, Orvieto E et al (2010) Diffuse leptomeningeal glioneuronal tumors: a new entity? Brain Pathol 20:361–366 However, in certain situations, superficial parenchyma or Virchow-Robin gaps were affected.Davila G, Duyckaerts C, Lazareth JP et al (1993) Diffuse primary leptomeningeal gliomatosis. J Neurooncol 15:45–49Kastenbauer S, Danek A, Klein W et al (2000) Primary diffuse leptomeningeal gliomatosis: unusual MRI with non-enhancing nodular lesions on the cerebellar surface and spinal leptomeningeal enhancement. J Neurol Neurosurg Psychiatry 69:385–388 Molecular and genetic investigations frequently show a combination of KIAA1549 and the serine/threonine protein kinase BRAF gene, and also deletions of the short arm of chromosome number 1 and/or the long arm of chromosome number 19.Rodriguez, F.J.; Schniederjan, M.J.; Nicolaides, T.; Tihan, T.; Burger, P.C.; Perry, A. High rate of concurrent BRAF-KIAA1549 gene fusion and 1p deletion in disseminated oligodendroglioma-like leptomeningeal neoplasms (DOLN). Acta Neuropathol. 2015, 129, 609–610
Clinical features Patients with DLGNT presented with a variety of clinical manifestations, depending on the involved area of the disease, ranging from, numbness and seizure to hydrocephalus symptoms Irritability, headaches and vomiting.Schniederjan MJ, Alghamdi S, Castellano-Sanchez A, Mazewski C, Brahma B, Brat DJ, Brathwaite CD, Janss AJ (2013) Diffuse leptomeningeal neuroepithelial tumor: 9 pediatric cases with chromosome 1p/19q deletion status and IDH1 (R132H) immunohistochemistry. Am J Surg Pathol 37:763–771. https://doi.org/10.1097/PAS.0b013e31827bf4ccDodgshun AJ, SantaCruz N, Hwang J, Ramkissoon SH, Malkin H, Bergthold G, Manley P, Chi S, MacGregor D, Goumnerova L et al (2016) Disseminated glioneuronal tumors occurring in childhood: treatment outcomes and BRAF alterations including V600E mutation. J Neurooncol 128:293–302. https://doi.org/10.1007/s11060-016-2109-x The progression of the disease is slow, however there have been reports of anaplastic transition.Yamasaki, T.; Sakai, N.; Shinmura, K.; Kawaji, H.; Koizumi, S.; Samashima, T.; Namba, H. Anaplastic changes of diffuse leptomeningeal glioneuronal tumor with polar spongioblastoma pattern. Brain Tumor Pathol. 2018, 35, 209–216.Schwetye, K.E.; Kansagra, A.P.; McEachern, J.; Schmidt, R.E.; Gauvain, K.; Dahiya, S. Unusual highgrade features in pediatric diffuse leptomeningeal glioneuronal tumor: Comparison with a typical low-grade example. Hum. Pathol. 2017, 70, 105–112.
Diagnosis MRI reveals broad leptomeningeal enhancing and thickness, which is frequently most visible throughout the spine, brainstem, and posterior fossa.Rossi S, Rodriguez FJ, Mota RA, Dei Tos AP, Di Paola F, Bendini M, Agostini S, Longatti P, Jenkins RB, Giannini C (2009) Primary leptomeningeal oligodendroglioma with documented progression to anaplasia and t(1;19) (q10;p10) in a child. Acta Neuropathol 118:575–577. https://doi.org/10.1007/s00401-009-0565-5
References