1. Department of Neurology, Research Institute and Hospital of National Cancer Center, Goyang, Gyeonggi 10408, Republic of Korea
2. Division of Clinical Research, Research Institute and Hospital of National Cancer Center, Goyang, Gyeonggi 10408, Republic of Korea
3. Biostatistics Collaboration Team, Research Institute and Hospital of National Cancer Center, Goyang, Gyeonggi 10408, Republic of Korea
4. Department of Neurosurgery, Research Institute and Hospital of National Cancer Center, Goyang, Gyeonggi 10408, Republic of Korea