**2. Incidence**

The incidence of childhood CNS tumor varies from 1.12 to 5.14 cases per 100,000 individuals [2]. Based upon data from the Central Brain Tumor Registry of the United States (CBTRUS), the estimated incidence of primary non-malignant and malignant CNS tumors for children and adolescents up to 19 years of age was 7.18 cases per 100,000 person-year in 2016 [3]. More than 100 different


#### **Table 1.**

*Common brain tumor types with location and frequency [5].*

histological subtypes of CNS tumours are recognized but their incidence varies with age. Incidence in Africa is around 11 per 10,00,000 and in Japan and Europe it ranges from 20 to 30 per 1,000,000. The male to female ratio is 1.25:1, as slightly higher frequency of medulloblastoma and CNS germinoma is seen in boys [4]. The most common histological subtypes along with location are mentioned below (**Table 1**).
