biostudies-literatureUnknown12(3)Mulhem A<h4>Key clinical message</h4>Primary GBM of the optic nerve and chiasma should be included in the differential diagnosis of progressive lesions despite initial treatment; clinicians should avoid delay in confirming the histology to initiate proper treatment and improve prognosis.<h4>Abstract</h4>Primary GBM of the optic nerve or chiasma is very rare. The characteristics of this condition have not been well-described, which poses difficulties in establishing the correct diagnosis, affecting the treatment and the prognosis. We present a case of GBM of the optic chiasma diagnosed through an open biopsy at our centre. Following the PRISMA statement, we also conducted a systematic review after protocol registration in PROSPERO (CRD42021285855). We searched Medline and Embase through Ovid from iClinical case reportse8636https://www.ebi.ac.uk/biostudies/studies/S-EPMC10954565biostudies-literaturePrimary glioblastoma multiform (GBM) of the optic nerve and chiasma: A case report and systematic review of the literature.PMC10954565Mulhem AfalsePrimary glioblastoma multiform (GBM) of the optic nerve and chiasma: A case report and systematic review of the literature.<h4>Key clinical message</h4>Primary GBM of the optic nerve and chiasma should be included in the differential diagnosis of progressive lesions despite initial treatment; clinicians should avoid delay in confirming the histology to initiate proper treatment and improve prognosis.<h4>Abstract</h4>Primary GBM of the optic nerve or chiasma is very rare. The characteristics of this condition have not been well-described, which poses difficulties in establishing the correct diagnosis, affecting the treatment and the prognosis. We present a case of GBM of the optic chiasma diagnosed through an open biopsy at our centre. Following the PRISMA statement, we also conducted a systematic review after protocol registration in PROSPERO (CRD42021285855). We searched Medline and Embase through Ovid from i2024-01-01T00:00:00Z2024 Mar2025-04-22T12:58:36.201Z2025-04-06T00:26:58.574ZS-EPMC109545653851599410.1002/ccr3.8636