Chondrosarcoma in Japan: an analytic study using population-based National Cancer Registry.

Background: Chondrosarcoma (CS) is a rare malignant bone tumor exhibiting diverse histological features and clinical behaviors. This study aimed to investigate the epidemiological characteristics, clinical features, prognostic factors, and subtype-specific differences of CS in Japan using National Cancer Registry data.

Methods: We analyzed data from CS cases diagnosed between 2016 and 2019, calculating age-adjusted incidence, estimating overall survival, and identifying prognostic factors through multivariate analysis.

Results: The study identified 1015 CS cases with an age-adjusted incidence of 0.159 per 100 000 population and a mean overall survival of 1205.2 days. Multivariate analysis revealed that female sex, younger age (15-39 years), histological subtypes other than dedifferentiated CS, localized disease, and surgical treatment were associated with better prognoses. Conversely, male sex, older age (≥75 years), dedifferentiated subtype, advanced stage, and non-surgical treatment were linked to a higher risk of death. Significant differences in sex distribution, age at diagnosis, tumor location, disease stage, and tumor differentiation were observed among CS subtypes.

Conclusion: This comprehensive analysis provides valuable insights into CS epidemiology, prognostic factors, and subtype-specific characteristics in Japan. The identification of high-risk groups emphasizes the need for improved therapeutic strategies and supportive care. The observed heterogeneity among CS subtypes underscores the importance of individualized management approaches in treating this complex malignancy.