Global incidence of malignant brain and other central nervous system tumors by histology, 2003-2007.

BACKGROUND: Previous reports have shown that overall incidence of malignant brain and other central nervous system (CNS) tumors varied significantly by country. The aim of this study was to estimate histology-specific incidence rates by global region and assess incidence variation by histology and age.

METHODS: Using data from the Central Brain Tumor Registry of the United States (CBTRUS) and the International Agency for Research on Cancer's (IARC) Cancer Incidence in Five Continents X (including over 300 cancer registries), we calculated the age-adjusted incidence rates (AAIR) per 100000 person-years and 95% CIs for brain and other CNS tumors overall and by age groups and histology.

RESULTS: There were significant differences in incidence by region. Overall incidence of malignant brain tumors per 100000 person-years in the US was 5.74 (95% CI = 5.71-5.78). Incidence was lowest in Southeast Asia (AAIR = 2.55, 95% CI = 2.44-2.66), India (AAIR = 2.85, 95% CI = 2.78-2.93), and East Asia (AAIR = 3.07, 95% CI = 3.02-3.12). Incidence was highest in Northern Europe (AAIR = 6.59, 95% CI = 6.52-6.66) and Canada (AAIR = 6.53, 95% CI = 6.41-6.66). Astrocytic tumors showed the broadest variation in incidence regionally across the globe.

CONCLUSION: Brain and other CNS tumors are a significant source of cancer-related morbidity and mortality worldwide. Regional differences in incidence may provide clues toward genetic or environmental causes as well as a foundation for broadening knowledge of their epidemiology. Gaining a comprehensive understanding of the epidemiology of malignant brain tumors globally is critical to researchers, public health officials, disease interest groups, and clinicians and contributes to collaborative efforts in future research.