Atypical presentation of massive glioblastoma mimicking rapidly progressive dementia

Glioblastoma can rarely present with predominantly psychiatric, cognitive, and behavioral symptoms, complicating timely diagnosis. This case describes a woman in her late 50s who developed abrupt-onset paranoia, memory impairment, and rapid neurological decline, initially misdiagnosed as rapidly progressive dementia with behavioral and psychological symptoms. Later, neuroimaging revealed a massive left fronto-temporoparietal glioblastoma with significant mass effect. Surgical excision and histopathology confirmed epithelioid glioblastoma (World Health Organization Grade IV) with tumor protein 53 and isocitrate dehydrogenase-1 mutations. Post-surgical recovery showed some neurological improvement, and she was referred for radiotherapy. This case highlights the diagnostic challenge of atypical brain tumor presentations and underscores the need for neuroimaging in patients with new-onset behavioral or cognitive symptoms, especially when neurological signs are present. Early recognition and intervention are critical in such cases to enable effective treatment and improve outcomes in aggressive brain tumors like glioblastoma.