Trends in net survival for patients with brain tumors in Japan, 2000-14 (CONCORD-3)

Brain tumors are a serious health issue, and survival is an effective indicator of how the healthcare system manages them. We examined net survival trends for patients diagnosed with a primary brain tumor during 2000-2014 in Japan, using data from 16 regional population-based cancer registries participating in the CONCORD-3 study.

We included patients aged 15-99 years, with follow-up completed either 5 years after diagnosis or up to 31 December, 2014. We estimated 5-year net survival by age group and morphological subtype using the Pohar Perme estimator, and age-standardized with International Cancer Survival Standard weights.

Five-year net survival for brain tumors increased from 27.9% for patients diagnosed during 2000-2004 to 46.3% in 2010-2014. During 2010-2014, 5-year net survival for astrocytic tumors was 22.3%, but ~90% for neuronal and mixed neuro-glial tumors, germ cell tumors, and other specified tumors. Five-year net survival reached 62.1% for oligodendroglial and oligoastrocytic tumors.

Five-year net survival for brain tumors in Japan improved during 2000-2014, with remarkable variations by morphologic type. Survival improved for all age groups, and particularly for younger patients, highlighting the need for enhanced survivorship care. Japan's focus on comprehensive data collection and supportive care for longer-term survivors remains key for further progress. When comparedinternationally, Japan's gains sit at the higher end of reported survival ranges, underscoring how robust registry infrastructure and equitable access to care could inform strategies for brain tumor care.