An unusual cause of dementia

Gliomatosis Cerebri: A Review of 296 Cases from the ANOCEF Database and the Literature

Gliomatosis cerebri (GC) is a rare disease, defined as a diffuse neoplastic glial cell infiltration of the brain. Diagnosis and management of GC are difficult. This study analyzed 296 individual cases (90 patients followed through the ANOCEF network, and 206 cases from the literature), aged 1 month to 85 years (median 42), sex ratio=1.31. Median survival was 14.5 months. It was higher for patients younger than 42 years (17 months vs. 13 months), with performance status>or=80 (27 months vs. 9 months), low grade gliomatosis (grade 2=20 months, grade 3=11.5 months, grade 4=8.5 months), oligodendroglial subtype (36 months compared to 14 months for mixed GC and 11 months for astrocytic GC). Male population was younger (median 39 years vs. 45), had a higher incidence of oligodendroglial GC (22% vs. 13%), which may explain their better prognosis (median survival 17 months vs. 11.5 months) than female population. Despite a high rate of stabilization, the impact on survival of whole brain radiotherapy, which carries the risk of severe toxicity, is still unclear. Up-front chemotherapy benefit to some patients and may be preferred to whole brain radiotherapy. However, the many bias of such retrospective heterogeneous data claim for multicentric clinical trials in this rare disease.

Diseases of white matter and schizophrenia-like psychosis

OBJECTIVE

To analyse the available data regarding the presentation of psychosis in diseases of central nervous system (CNS) white matter.

METHOD

The available neurological and psychiatric literature on developmental, neoplastic, infective, immunological and other white matter diseases was reviewed.

RESULTS

A number of diseases of the white matter can present as schizophrenia-like psychoses, including leukodystrophies, neoplasms, velocardiofacial syndrome, callosal anomalies and inflammatory diseases.

CONCLUSIONS

Production of psychotic symptoms may result from functional asynchrony of interdependent regions, due to alterations in critical circuits as a result of pathology. The nature, location and timing of white matter pathology seem to be the key factors in the development of psychosis, especially during the critical adolescent period of association area myelination. Diseases that disrupt the normal formation of myelin appear to cause psychosis at higher rates than those that disrupt mature myelinated structures. Diffuse rather than discrete lesions, in particular those affecting frontotemporal zones, are also more strongly associated with schizophrenia-like psychosis. These illnesses point to the central role that white matter plays in maintaining CNS connectivity and to how pathology of the white matter may contribute to the neurobiology of psychosis.

Gliomatosis cerebri: neurobehavioral and neuropathological observations

BACKGROUND

Gliomatosis cerebri is a rare neoplasm in which individual neoplastic cells diffusely permeate the brain; a cohesive tumor mass may appear late in the disease course, or not at all. The diagnosis can be made either at autopsy or premortem by combining biopsy and neuroimaging findings to demonstrate involvement of more than two lobes of the brain. Extensive hemispheric white matter and corpus callosum infiltration is characteristic, with lesser spread to subcortical and cortical gray matter. Whereas this pattern of localization can be predicted to cause significant disturbances of higher function, the neurobehavioral profile of gliomatosis cerebri patients has not been well described.

METHOD

Three patients with gliomatosis cerebri had detailed neurobehavioral assessment, and one had neuropsychological testing early in the disease. Neuropathological investigation focused on the localization of the neoplasm, the correlation between extent of myelin and axon damage with tumor cell density, and the histogenesis of the tumor.

RESULTS

The patient with neuropsychological testing had impaired executive function and verbal memory retrieval that reflected bifrontal and left temporal white matter tumor involvement seen on neuroimaging. In the other cases, apathy and fatigue progressed to severe dementia in association with bihemispheric white matter infiltration. Myelin and axon stains and myelin stains showed relative preservation of white matter architecture with severity of damage paralleling increased tumor cell density. Immunostaining for TP53 was found in a high percentage of tumor nuclei in two of three cases, suggesting overlapping features between gliomatosis cerebri and diffuse astrocytomas.

CONCLUSIONS

Subtle cognitive and emotional alterations antedate the florid dementia that develops later in the course of gliomatosis cerebri. Clinical, neuroimaging, and neuropathological data suggest that white matter is damaged directly by the tumor and its associated mild edema, although infiltration of subcortical and cortical gray matter also occurs to a variable extent. Strong TP53 immunostaining in gliomatosis cerebri suggests a commonality with diffuse fibrillary astrocytomas that also often show TP53 staining. Gliomatosis cerebri can be considered a cause of white matter dementia resulting from preferential neoplastic disruption of white matter tracts.

Psychiatric manifestations of systemic illness

Many behavioral manifestations of systemic disease exist, including delirium, psychosis, mania, catatonia, depression, and anxiety. The features and medical causes of each of those manifestations are described. The indications from history and physical examination that suggest underlying medical illness are reviewed. The psychiatric presentations of several specific conditions are discussed in detail.