Epidemiology and long-term survival of primary central nervous system germ cell tumors in Korea: a nationwide population-based study, 2005-2022.

Background Primary central nervous system germ cell tumors (CNSGCTs) are rare neoplasms that predominantly affect adolescents, and young adults. However, large population-based data remain limited. To address this gap, the latest epidemiologic and long-term survival data for newly diagnosed CNSGCTs in Korea from 2005 to 2022 were analyzed. Methods We sourced epidemiological and survival data on primary CNSGCTs using the Korea National Cancer Incidence Database (KNCI DB), a nationwide population-based cancer registry. Incidence and survival outcomes were compared with those reported in recent CBTRUS Statistical Reports from the United States (US) and previous epidemiologic studies from Japan. Results A total of 1,642 newly diagnosed primary CNSGCTs were identified. There was a marked male predominance, with the highest incidence observed in the 10-14 and 15-19 age groups. Germinoma was the predominant histopathologic subtype across all age groups, except in the 0-4 and 30+ age groups, where the proportion of teratomas was relatively high. The overall incidence of CNSGCTs remained stable throughout the study period. The 1-, 5-, 10-, and 15-year relative survival rates were 95.4%, 89.6%, 87.1%, and 84.6%, respectively, with germinomas showing the most favorable prognosis. The incidence of primary CNSGCTs was significantly higher in Korea than in the US. Long-term outcomes were excellent and comparable to those reported from the US and Japan. Conclusion The overall incidence of CNSGCTs was significantly higher in Korea, with favorable long-term survival outcomes. Distinct patterns and significant differences in survival outcomes were observed across different age groups and histopathologic subtypes.