{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,14]],"date-time":"2026-08-14T16:34:25Z","timestamp":1786725265030,"version":"build-2736575974"},"reference-count":36,"publisher":"MDPI AG","issue":"16","license":[{"start":{"date-parts":[[2026,8,14]],"date-time":"2026-08-14T00:00:00Z","timestamp":1786665600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Diagnostics"],"abstract":"<jats:p>Background\/Objectives: In glioma patients, acute neurologic deterioration may reflect nonconvulsive status epilepticus (NCSE), peri-ictal pseudoprogression, treatment-related change, or true progression. As these entities share imaging features, misdiagnosis can delay therapy. This review synthesizes evidence relevant to a proposed electroclinical-imaging framework for distinguishing seizure-related deterioration from treatment-related change and true progression. Methods: This narrative review synthesized English-language literature on tumor-related epilepsy, NCSE, peri-ictal imaging abnormalities, pseudoprogression, radiation necrosis, Response Assessment in Neuro-Oncology (RANO) criteria, and advanced imaging in adult diffuse glioma. Results: Seizure recurrence after glioma treatment may indicate tumor activity, but it may also reflect radiation injury, postoperative gliosis, edema, metabolic disturbance, medication effects, or transient peri-ictal change. NCSE is particularly important because it may present with aphasia, confusion, impaired consciousness, behavioral change, or deficits without convulsions, making electroencephalography central for unexplained deterioration. Seizure activity can also produce transient magnetic resonance imaging (MRI) or positron emission tomography (PET) abnormalities, including enhancement, fluid-attenuated inversion recovery (FLAIR) hyperintensity, diffusion restriction, and perfusion changes that mimic recurrence. Conclusions: This review proposes a structured electroclinical-imaging framework incorporating early EEG, seizure history, treatment timing, corticosteroid and antiseizure response, multimodal imaging, and longitudinal reassessment for prospective evaluation in treated glioma patients with new neurologic decline.<\/jats:p>","DOI":"10.3390\/diagnostics16162572","type":"journal-article","created":{"date-parts":[[2026,8,14]],"date-time":"2026-08-14T15:48:36Z","timestamp":1786722516000},"page":"2572","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Seizure-Related Deterioration in Treated Glioma: A Narrative Review of Nonconvulsive Status Epilepticus, Peri-Ictal Pseudoprogression, Treatment-Related Change, and True Progression"],"prefix":"10.3390","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0009-0004-7219-784X","authenticated-orcid":false,"given":"Polina","family":"Chliapnikov","sequence":"first","affiliation":[{"name":"Division of Neurosurgery, Toronto Western Hospital, University of Toronto, 399 Bathurst St., Toronto, ON M5T 2S8, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mark","family":"Bernstein","sequence":"additional","affiliation":[{"name":"Division of Neurosurgery, Toronto Western Hospital, University of Toronto, 399 Bathurst St., Toronto, ON M5T 2S8, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,8,14]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1231","DOI":"10.1093\/neuonc\/noab106","article-title":"The 2021 WHO classification of tumors of the central nervous system: A summary","volume":"23","author":"Louis","year":"2021","journal-title":"Neuro-Oncology"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"170","DOI":"10.1038\/s41571-020-00447-z","article-title":"EANO guidelines on the diagnosis and treatment of diffuse gliomas of adulthood","volume":"18","author":"Weller","year":"2021","journal-title":"Nat. Rev. Clin. Oncol."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"987","DOI":"10.1056\/NEJMoa043330","article-title":"Radiotherapy plus concomitant and adjuvant temozolomide for glioblastoma","volume":"352","author":"Stupp","year":"2005","journal-title":"N. Engl. J. Med."},{"key":"ref_4","doi-asserted-by":"crossref","unstructured":"Solar, P., Hendrych, M., Barak, M., Valekova, H., Hermanova, M., and Jancalek, R. (2022). Blood-brain barrier alterations and edema formation in different brain mass lesions. Front. Cell. Neurosci., 16.","DOI":"10.3389\/fncel.2022.922181"},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"7","DOI":"10.1093\/neuonc\/noad154","article-title":"Brain tumor-related epilepsy management: A Society for Neuro-Oncology (SNO) consensus review on current management","volume":"26","author":"Avila","year":"2023","journal-title":"Neuro-Oncology"},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"542","DOI":"10.1016\/j.seizure.2014.04.003","article-title":"Nonconvulsive status epilepticus in patients with brain tumors","volume":"23","author":"Marcuse","year":"2014","journal-title":"Seizure"},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"775","DOI":"10.1093\/neuonc\/nor082","article-title":"Peri-ictal pseudoprogression in patients with brain tumor","volume":"13","author":"Rheims","year":"2011","journal-title":"Neuro-Oncology"},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"19","DOI":"10.1016\/j.seizure.2017.05.005","article-title":"An exploration of the spectrum of peri-ictal MRI change; a comprehensive literature review","volume":"50","author":"Williams","year":"2017","journal-title":"Seizure"},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"779","DOI":"10.1093\/neuonc\/nov269","article-title":"Epilepsy in glioma patients: Mechanisms, management, and impact of anticonvulsant therapy","volume":"18","author":"Armstrong","year":"2016","journal-title":"Neuro-Oncology"},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"30","DOI":"10.1007\/s12672-023-00632-3","article-title":"Nonconvulsive status epilepticus characteristics in glioma patients: A retrospective study","volume":"14","author":"Kaneoka","year":"2023","journal-title":"Discov. Oncol."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"158","DOI":"10.1016\/j.yebeh.2015.05.007","article-title":"Salzburg consensus criteria for non-convulsive status epilepticus\u2014Approach to clinical application","volume":"49","author":"Leitinger","year":"2015","journal-title":"Epilepsy Behav."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1097\/WNP.0000000000000806","article-title":"American Clinical Neurophysiology Society\u2019s standardized critical care EEG terminology: 2021 version","volume":"38","author":"Hirsch","year":"2021","journal-title":"J. Clin. Neurophysiol."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"571","DOI":"10.1002\/jmri.26171","article-title":"Pseudoprogression of brain tumors","volume":"48","author":"Thust","year":"2018","journal-title":"J. Magn. Reson. Imaging"},{"key":"ref_14","first-page":"1550","article-title":"Diagnostic performance of PET and perfusion-weighted imaging in differentiating tumor recurrence or progression from radiation necrosis in posttreatment gliomas: A review of literature","volume":"41","author":"Soni","year":"2020","journal-title":"Am. J. Neuroradiol."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"540","DOI":"10.1007\/s00259-018-4207-9","article-title":"Joint EANM\/EANO\/RANO practice guidelines\/SNMMI procedure standards for imaging of gliomas using PET with radiolabelled amino acids and [18F]FDG: Version 1.0","volume":"46","author":"Law","year":"2019","journal-title":"Eur. J. Nucl. Med. Mol. Imaging"},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"1963","DOI":"10.1200\/JCO.2009.26.3541","article-title":"Updated response assessment criteria for high-grade gliomas: Response Assessment in Neuro-Oncology Working Group","volume":"28","author":"Wen","year":"2010","journal-title":"J. Clin. Oncol."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"5","DOI":"10.1186\/s41073-019-0064-8","article-title":"SANRA-a scale for the quality assessment of narrative review articles","volume":"4","author":"Baethge","year":"2019","journal-title":"Res. Integr. Peer Rev."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"1277","DOI":"10.1200\/JCO.1990.8.7.1277","article-title":"Response criteria for phase II studies of supratentorial malignant glioma","volume":"8","author":"Macdonald","year":"1990","journal-title":"J. Clin. Oncol."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"5187","DOI":"10.1200\/JCO.23.01059","article-title":"RANO 2.0: Update to the Response Assessment in Neuro-Oncology criteria for high- and low-grade gliomas in adults","volume":"41","author":"Wen","year":"2023","journal-title":"J. Clin. Oncol."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"1423","DOI":"10.1093\/neuonc\/noac003","article-title":"IDH-mutated gliomas promote epileptogenesis through d-2-hydroxyglutarate-dependent mTOR hyperactivation","volume":"24","author":"Mortazavi","year":"2022","journal-title":"Neuro-Oncology"},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"1269","DOI":"10.1038\/nm.2453","article-title":"Glutamate release by primary brain tumors induces epileptic activity","volume":"17","author":"Buckingham","year":"2011","journal-title":"Nat. Med."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"696","DOI":"10.1016\/j.neuint.2013.01.027","article-title":"Glutamate and tumor-associated epilepsy: Glial cell dysfunction in the peritumoral environment","volume":"63","author":"Buckingham","year":"2013","journal-title":"Neurochem. Int."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"454","DOI":"10.1093\/neuonc\/noaf165","article-title":"RANO Seizure Working Group-tumor-related epilepsy assessment tool (RANO-TREAT) to assess seizure control for glioma treatment trials and clinical practice","volume":"28","author":"Avila","year":"2026","journal-title":"Neuro-Oncology"},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"12","DOI":"10.1093\/neuonc\/now190","article-title":"Seizure control as a new metric in assessing efficacy of tumor treatment in low-grade glioma trials","volume":"19","author":"Avila","year":"2017","journal-title":"Neuro-Oncology"},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"vdaf237","DOI":"10.1093\/noajnl\/vdaf237","article-title":"Seizure outcomes as an understudied metric in glioma clinical trials: A review of the ClinicalTrials.gov database","volume":"8","author":"Haile","year":"2026","journal-title":"Neuro-Oncol. Adv."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"1515","DOI":"10.1111\/epi.13121","article-title":"A definition and classification of status epilepticus\u2014Report of the ILAE Task Force on Classification of Status Epilepticus","volume":"56","author":"Trinka","year":"2015","journal-title":"Epilepsia"},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"76","DOI":"10.1016\/j.seizure.2016.06.013","article-title":"Status epilepticus secondary to glioma","volume":"40","author":"Power","year":"2016","journal-title":"Seizure"},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"106370","DOI":"10.1016\/j.yebeh.2019.06.014","article-title":"Tumor-associated status epilepticus in patients with glioma: Clinical characteristics and outcomes","volume":"101","author":"Giovannini","year":"2019","journal-title":"Epilepsy Behav."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"48","DOI":"10.1016\/j.seizure.2023.09.014","article-title":"Status epilepticus in patients with glioblastoma: Clinical characteristics, risk factors, and epileptological outcome","volume":"112","author":"Stritzelberger","year":"2023","journal-title":"Seizure"},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"19","DOI":"10.1186\/s42466-024-00314-7","article-title":"Status epilepticus in patients with brain tumors and metastases: A multicenter cohort study of 208 patients and literature review","volume":"6","author":"Rickel","year":"2024","journal-title":"Neurol. Res. Pract."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"229","DOI":"10.1177\/19714009231166105","article-title":"Post-ictal changes presenting as late pseudoprogression on MRI and PET in a patient with diffuse glioma: Case report and brief literature review","volume":"37","author":"Nair","year":"2024","journal-title":"Neuroradiol. J."},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"33","DOI":"10.1007\/s11916-021-00946-3","article-title":"Stroke-like migraine attacks after radiation therapy (SMART) syndrome: A comprehensive review","volume":"25","author":"Dominguez","year":"2021","journal-title":"Curr. Pain. Headache Rep."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"405","DOI":"10.1002\/cncr.23562","article-title":"Incidence of early pseudo-progression in a cohort of malignant glioma patients treated with chemoirradiation with temozolomide","volume":"113","author":"Taal","year":"2008","journal-title":"Cancer"},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"2192","DOI":"10.1200\/JCO.2007.14.8163","article-title":"MGMT promoter methylation status can predict the incidence and outcome of pseudoprogression after concomitant radiochemotherapy in newly diagnosed glioblastoma patients","volume":"26","author":"Brandes","year":"2008","journal-title":"J. Clin. Oncol."},{"key":"ref_35","doi-asserted-by":"crossref","unstructured":"Alizadeh, M., Broomand Lomer, N., Azami, M., Khalafi, M., Shobeiri, P., Arab Bafrani, M., and Sotoudeh, H. (2023). Radiomics: The new promise for differentiating progression, recurrence, pseudoprogression, and radionecrosis in glioma and glioblastoma multiforme. Cancers, 15.","DOI":"10.3390\/cancers15184429"},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"e436","DOI":"10.1016\/S1470-2045(25)00193-7","article-title":"Update to the RANO Working Group and EANO recommendations for the clinical use of PET imaging in gliomas","volume":"26","author":"Galldiks","year":"2025","journal-title":"Lancet Oncol."}],"container-title":["Diagnostics"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2075-4418\/16\/16\/2572\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,8,14]],"date-time":"2026-08-14T15:56:10Z","timestamp":1786722970000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2075-4418\/16\/16\/2572"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,8,14]]},"references-count":36,"journal-issue":{"issue":"16","published-online":{"date-parts":[[2026,8]]}},"alternative-id":["diagnostics16162572"],"URL":"https:\/\/doi.org\/10.3390\/diagnostics16162572","relation":{},"ISSN":["2075-4418"],"issn-type":[{"value":"2075-4418","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,8,14]]}}}