To the Editor: Schizophrenia-like psychosis is often reported in association with glial or congenital tumors in the temporal lobe, particularly gangliogliomas and dysembryoblastic neuroepitheliomas.¹ In this study, we report on a patient who developed schizophrenia-like psychosis associated with a right parietal meningioma.

A right-handed woman with no personal or family history of psychosis suffered from simple partial sensory seizures involving the left extremities with frequent secondarily generalized tonic–clonic seizures since the age of 35. She was diagnosed with a right-parasagittal parietal meningioma, and subsequently underwent surgery, which resulted in seizure frequency-reduction >90%. Six years later, at the age of 41, the neurological condition of the patient deteriorated, with significant increase in seizure frequency, and development of left hemiparesis and schizophrenia-like psychosis. Brain MRI revealed recurrence of a large meningioma, and another surgery was performed. After surgery, the patient became seizure-free. The psychotic symptoms were characterized by severe paranoid delusions of persecution and reference related to her neighbors and family members, and auditory hallucinations, to a lesser extent. Schizoaffective disorder and mood disorder (e.g., major depression) with psychotic features were ruled out. After initiation of treatment with antipsychotics (i.e., risperidone), the psychotic symptoms showed gradual improvement. Postoperative magnetoencephalography showed no epileptic discharge but prominent delta/theta activity surrounding the tumor, likely representing perilesional edema and dysfunctional cortex.

Tumoral lesions, especially gangliogliomas and dysembryoblastic neuroepitheliomas, are commonly seen in the excised tissues of patients undergoing temporal lobe surgery who present with schizophrenia-like symptoms.¹ However, extratemporal tumors have rarely been reported to be associated with schizophrenia-like disorders. In this study, we describe a patient who developed schizophrenia-like psychosis along with neurological deterioration associated with recurrence of a right parietal meningioma. A few studies have reported that right-sided tumors, including meningiomas affecting the parietal cortex² were found in patients with delusional schizophrenia-like disorders. This is consistent with recent evidence indicating that the right parietal cortex is implicated in the pathogenesis of delusions and schizophrenia-like symptoms.³ In this context, it is interesting that our patient presented with a psychotic disorder with predominant paranoid delusions. Further, post-mortem finding of right parietal meningioma in patients with a diagnosis of schizophrenia have suggested a possible causal relationship between chronic psychosis and meningioma-related parietal dysfunction.⁴

Our finding illustrates that tumors, including meningiomas, located in extratemporal regions, specifically in the right parietal lobe, may be associated with chronic psychosis in some vulnerable patients, thus highlighting a role not only for reported temporal lesions but also for right-parietal abnormalities in the development of schizophrenia-like disorders.