A total of 11,827 brain and CNS patients were registered in 2013 from 396 hospitals. Basic information such as the demographic characteristics of patients, date of diagnosis, tools of diagnosis, topography, and histological type according to the ICD-O-3 were collected by the KCCR [1].

Primary brain and CNS tumors with the following ICD-O-3 codes were included in the analysis: brain (C71.0–C71.9), meninges (C70.0–C70.9), spinal cord, cranial nerves and other parts of the CNS (C72.0–C72.9), and pituitary gland, craniopharyngeal duct and pineal gland (C75.1–C75.3). Their histology code was also classified by the ICD-O-3, which are divided into 3 groups: benign, uncertain whether benign or malignant (borderline), and malignant.

Histology groupings were based on the classification of the CBTRUS [3]. These groupings were broadly based on the World Health Organization categories for brain tumors. Unclassified tumors include unspecified neoplasms and all other tumors. Unspecified neoplasms refer to cases registered based on death certificates only. The tumors which classified into all other tumors were tumors that did not meet the CBTRUS criteria.

The population size used as a denominator to calculate cancer incidence was the mid-year population on 1 July 2013 with modification of the registered population released annually from the Statistics Korea [13]. Childhood tumors were defined as those diagnosed in patients less than 19 years of age.

Incidence measures the occurrence of newly diagnosed cases of disease. Crude rate is the rate of disease in an entire population and it is frequently adjusted for age to age-standardized rate to a common standard population, which allows for comparison of rates across different countries with different age structures. We used Segi's world standard population as a standard population in this report [14].

There were 11,827 newly diagnosed brain tumors from a population of 50.6 million in 2013 (Table 1). The overall crude rate of brain tumors was 23.39 per 100,000 person-years in 2013.

The incidence of meningiomas was over 3.5 times higher in females than in males. Nerve sheath tumors, pituitary tumors, andependymomas were also more common in females. On the other hand, germ cell tumors, gliomas (except pilocytic astrocytoma), and lymphomas were more common in males. Unclassified tumors accounted for 13.9% of all CNS tumors. The number of histological confirmed cases were 5,649 (47.8%) (Table 2). Pituitary tumors and nerve sheath tumors, accounted for 19.9% and 13.8% of all histologically confirmed tumors, respectively.

The overall incidence according to biological behavior is shown in Fig. 1. Tumors classified as benign, uncertain, and malignant tumors accounted for 73.2%, 8.8%, and 18.0% of all primary CNS tumors, respectively. The incidence in males was 37.1% and the incidence in females was 62.9%. Benign tumors developed nearly twice more frequently in females than in males (M:F=2,786:5,877). In contrast, the incidences of borderline tumors were noted to be similar.

The incidence according to the originating site is shown in Fig. 2. Meninges (35.2%) were the most common site of primary brain tumors, followed by the brain parenchyma (29.0%), sellar region (21.1%), and cranial and spinal nerves (14.7%). Tumors of the meninges developed more than 3 times frequently in females (Fig. 2). The sellar region tumorsshowed 1.5 times incidence of males than females. The other sites showed no significant differences in incidence according to sex. The overall incidence of primary brain tumors increased with age until the sixth decade. The incidence of each site specific tumor according to age is shown in Fig. 3. Tumorsof the brain parenchyma reached a peak in the sixth decade. Tumors of the meninges seldom occurred in childhood, the incidence of which increased from the third decade and peaked in the sixth decade. Tumors of the nerves peaked in the sixth decade. Sellar tumors increased rapidly in late adolescents and peaked in the sixth decade, which decreased thereafter.

Distribution of the tumors according to histology is shownin Fig. 4 and 5. Histologically, tumors of meninges were the most common (37.9%), followed by tumors of the sellar region (19.3%) and neuroepithelial tumors (13.6%).Neuroepithelial tumors of neuroepithelial tissue were composed of astrocytic tumors, oligodendroglial tumors, ependymal tumors, choroid plexus tumors, pineal region tumors, and embryonal tumors. Most of the neuroectodermal tumors were gliomas (93.4%), which accounted for 12.7% of all primary brain tumors. Glioblastomas accounted for 5.3% of all tumors and 41.8% of allgliomas. Among histologically confirmed cases, glioblastomas accounted for 46.2% of all gliomas (Table 3).

Distribution of tumors according to histology in childhood is shown in Table 4 and Fig. 6.

Children numbering 578 under 19 years of age were diagnosed with brain tumors in 2013, and crude rates of primary brain tumors in children was 5.27 per 100,000 person-years. The incidence was slightly higher in females (5.17) than in males (5.03). The most common histology in children included neuroepithelial tumors, germ cell tumors, and tumors of thesellar region. Neuroepithelial tumors accounted for 38.6% of all tumors in children. Embryonal/primitive/medulloblastoma was the most common tumor among neuroepithelial tumors in children. Glioblastomas accounted for only 3.3% of all primary brain tumors in children.