Search

Introduction: Gliomatosis cerebri (GC) is a rare fatal widespread infiltrating CNS tumor. As consistent disease features have not been established, the tumor comprises a diagnostic challenge., Methods: We conducted a systematic literature search for published case reports and case series on patients with histologically confirmed GC. Clinical, diagnostic, neuroimaging, histopathological, and molecular data on individual or summary patient level were extracted and analyzed., Results: A total of 274 studies were identified, including 866 patients with individual-level data and 782 patients with summary data (58.9% males, mean age 43.6 years). Seizures (49.8%) were the most common presenting symptom followed by headache (35.9%), cognitive decline (32.2%), and focal motor deficits (32%). Imaging studies showed bilateral hemisphere involvement in 65%, infratentorial infiltration in 29.9% and a focal contrast-enhanced mass (type II GC) in 31.1% of cases. MRI (extensive hyperintensities in T2/FLAIR sequences) and MR spectroscopy (elevated choline, creatinine, and myoinositol levels; decreased NAA levels) showed highly consistent findings across GC patients. Low-grade and anaplastic astrocytoma were the most prevalent diagnostic categories, albeit features of any histology (astrocytic, oligodendroglial, oligoastrocytic) and grade (II-IV) were also reported. Among molecular aberrations, IDH1 mutation and MGMT promoter methylation were the most commonly reported. Increasing time elapsed from symptom onset to diagnosis comprised the only independent determinant of the extent of CNS infiltration., Conclusion: A distinct clinical, neuroimaging, histopathological, or molecular GC phenotype is not supported by current evidence. MRI and MR spectroscopy are important tools for the diagnosis of the tumor before confirmation with biopsy.

Gliomatosis cerebri (GC) comprises a rare widespread infiltrating growth pattern of diffuse gliomas. We explored the incidence patterns and survival rates of GC in a population-based registration sample from the Surveillance, Epidemiology and End, Results database (1973-2012). GC cases (n = 176) were identified based on their International Classification of Diseases in Oncology (ICD-O-3) morphology code (9381). We calculated age-adjusted incidence rates (AIR) and evaluated temporal trends. Survival was assessed with Kaplan-Meier curves and Cox regression models. The annual AIR of GC was 0.1/million. We noted increasing trends in the preceding registration years (1973-2002; annually, + 7%) and a tendency of clinical/radiological approaches to substitute the gold-standard histological assessment for diagnosis. GC was diagnosed in the entire age spectrum (range 1-98 years), but higher incidence rates (0.43/million) were noted among the elderly (≥ 65 years). A slight male preponderance was identified (male-to-female ratio: 1.4). Median overall survival was 9 months with a 5 year survival rate of 18%. Increasing age, primary tumor location not restricted to the cerebral hemispheres and rural residence at diagnosis were identified as negative prognostic factors, whereas receipt of radiotherapy, surgical treatment, race and method of diagnosis were not associated with outcome. This first comprehensive overview of GC epidemiology exemplifies the rarity of the disease, provides evidence for male preponderance and increased incidence among the elderly and shows lower survival rates compared to the published single center reports. Expansion of registration to histological and molecular characteristics would allow emergence of clinical prognostic factors at the population level.