https://repositorio.fleni.org.ar/xmlui/handle/123456789/570 Sun, 05 Apr 2026 19:28:12 GMT 2026-04-05T19:28:12Z https://repositorio.fleni.org.ar/xmlui/handle/123456789/1135 Hyaline eosinophilic astrocytic inclusions in two children with drug-resistant epilepsy—Case reports and literature review Mezmezian, Mónica Beatriz; Arakaki, Naomi; Yáñez, Paulina; Arias Cebollada, Eugenia; Muro, Valeria L.; Sevlever, Gustavo Emilio Introduction: Hyaline eosinophilic astrocytic inclusion (HEAI) is a rare histological finding in cases with drugresistant epilepsy (DRE). Objectives: To describe two cases of DRE with HEAI and review the literature. Patients and Methods: Case 1: A 5-year-old boy with a history of DRE since 5 months of age and global developmental delay, nonverbal (GDD, NV). MRI revealed signs of polymicrogyria, involving the right frontal operculum with an abnormal cortical folding and rotation pattern. The genetic panel showed a variant of uncertain significance in the SCL2A1 gene. Outcome: Engel IV-B. Case 2: A 5-year-old boy with a history of DRE since 4 months of age and GDD, NV. MRI showed abnormal cortical folding and cortical thickening in the right frontal lobe. Genetic testing demonstrated a variant of uncertain significance in the ADAR gene. Outcome: Engel IV-A. Resection of the lesion was performed in both patients. Results: Both cases showed brightly eosinophilic structures within the astrocytic cytoplasm in the gray matter and FCD type 2A. The inclusions were negative with PAS and Congo red. By immunohistochemistry, they were positive for S100 and negative for vimentin, and GFAP. We also analyzed the data of all the previously reported cases. Conclusion: HEAI is a rare entity, with only 53 cases reported, including our cases. Evaluating all the cases, the average age at seizure onset of pediatric patients (n = 48) was 7 months, without sex predilection. Seven patients had Aicardi syndrome, and 23 patients presented GDD. Seizures were observed in 47 patients. Outcome Engel: I in 10 cases, II in 5, III in 9, and IV in 9. Most cases involved the frontal lobe (n = 40). HEAIs were positive for S100 in 21/25 (84%), filamin in 22/25 (88%), GFAP in 3/32 cases (9%), vimentin in 1/16 (6%), and PAS in 3/21 (14%). FCD was observed in 19/50 patients (38%). The significance of HEAI is not clear. Genetic studies of the surgical specimens will probably allow a better comprehension of this entity. Wed, 13 Sep 2023 00:00:00 GMT https://repositorio.fleni.org.ar/xmlui/handle/123456789/1135 2023-09-13T00:00:00Z https://repositorio.fleni.org.ar/xmlui/handle/123456789/1134 Analysis of the implementation of DNA methylation assay for routine CNS tumors diagnosis Mezmezian, Mónica Beatriz; Arakaki, Naomi; Sevlever, Gustavo Emilio; Martinetto, Horacio Introduction: In the last years, DNA methylation array emerged as a new tool for CNS tumor diagnosis. Objectives: To analyze the value of methylation assay for routine CNS tumor diagnosis. Patients and Methods: We performed methylation array in 182 CNS tumors (100 gliomas (GL), 27 medulloblastomas (MDB), 20 ependymomas (EP), 17 neuronal/ glioneuronal tumors (N/GNT), 5 meningiomas, 7 embryonal tumors (ET), and 6 sarcomas) from 2019 for subtyping GL, EP, MDB, meningiomas, and sarcomas, defining the diagnosis in cases without precise histological features or confirming the histological diagnosis. Results: Scores were >0.75 in 147 cases (81%). The histological diagnosis was maintained and allowed subtyping in 127 cases (70%) (77 GL, 27 MDB, 12 EP, etc.), defined differential diagnoses in 16 cases (9%) (3 sarcomas, 5 ET, 3 EP, etc.), and changed the diagnosis in 4 cases (2%). Scores were ≤0.75 in 35 cases (19%), however, in 7/14 adult diffuse GL, CNV analysis (EGFR amplification, and Chr.10q and CDKN2A/B deletions) led to the diagnosis of the cases as IDH-wt glioblastomas based on the WHO classification. In 8/35 cases displaying scores ≤0.75, RNA and/or DNA sequencing was performed and led to the diagnosis of 4 tumors (1 sarcoma, 2 DMG H3K27-altered, and 1 pilocytic astrocytoma). Thus, in 24 cases (13%) diagnosis could not be achieved; among these cases, 10 were N/GNT. Conclusion: The methylation array is a valuable tool to diagnose most CNS tumors because a single technique offers both the diagnosis and molecular data, mainly for adult diffuse GL, MDB, and EP. Nowadays, the main limitations of the method are the high amount of DNA necessary for performing the study, economic issues for developing countries, and the absence in the classifier of uncommon tumors, such as low-grade N/GNT, and some of the new tumors of the 2021 WHO classification. The growth of the case base will improve the identification skills of the system, probably perfecting its diagnostic capabilities. Wed, 13 Sep 2023 00:00:00 GMT https://repositorio.fleni.org.ar/xmlui/handle/123456789/1134 2023-09-13T00:00:00Z https://repositorio.fleni.org.ar/xmlui/handle/123456789/571 AML-005: Primary Central Nervous System Myeloid Sarcoma Evolving from a Myeloid Neoplasm with Eosinophilia Associated with FIP1L1-PDGFRA Barbona, María Emilia; Freue, Julian; Enciso, Claudio; Fernández, María Margarita; Castro, Martín; Arakaki, Naomi; Sevlever, Gustavo Emilio; Campestri, Reinaldo Manuel Tue, 01 Sep 2020 00:00:00 GMT https://repositorio.fleni.org.ar/xmlui/handle/123456789/571 2020-09-01T00:00:00Z