Primary brain tumour epidemiology in Georgia: first-year results of a population-based study

A population-based cohort study was initiated in Georgia in March 2009 to collect epidemiologic data of malignant and non-malignant primary brain tumours. During the first year, 473 incident cases were identified. For a population of 4.3 million, the annual incidence rate was 10.25 per 100,000 inhabitants, age-standardized to the year 2000 US population. Non-malignant tumours constituted about 66 % of all tumours. Males accounted for 40 % and females for 60 % of the cases. Crude incidence rates by histology were highest for meningiomas (2.92/100,000), pituitary adenoma (1.16/100,000) and glioblastomas (0.64/100,000), which was in agreement with the frequency of reported histology: meningiomas—45.2 %, pituitary adenoma—18.0 % and glioblastomas—9.9 %. The age-standardized incidence rates were higher among females than males for all primary brain tumours (11.05 vs. 8.44/100,000) as well as for individual histologies except for glioblastoma and several other neuroepithelial tumours. Some differences compared with 2004–2005 Central Brain Tumor Registry of the United States data may be explained by a higher percentage of unclassified tumours (37 %) in our study. We suggest further studies to clarify the nature of this discrepancy.