Incidence trends, mortality, and treatment-related toxicity in osteosarcoma, neuroblastoma, and acute lymphoblastic leukemia in Kazakhstan

Pediatric cancer survival has improved substantially worldwide; however, evolving incidence patterns and treatment-related toxicity continue to challenge health systems, particularly in transitioning settings. This study evaluated population-level trends and clinical toxicity patterns of osteosarcoma, neuroblastoma, and acute lymphoblastic leukemia (ALL) in Kazakhstan.

A retrospective population-based epidemiological analysis was combined with a hospital-based clinical cohort study. Incidence and mortality data were obtained from the national cancer registry maintained by the Scientific Center for Health Development for 2016-2025. Temporal trends were analyzed using Poisson regression, and annual percent change (APC) was calculated. Forecasts for 2025-2030 were generated using regression-based models. Clinical data on treatment-related toxicity were retrospectively collected from medical records of patients treated at the National Scientific Center of Pediatrics and Pediatric Surgery. Multivariable logistic regression models were used to identify predictors of severe hematologic toxicity and related clinical outcomes.

Between 2016 and 2025, the incidence increased significantly for osteosarcoma (APC 18.2%, 95% CI 8.8-28.4; p = 0.0001) and neuroblastoma (APC 10.3%, 95% CI 5.0-15.9; p = 0.0001), while ALL demonstrated a non-significant upward trend. Mortality remained statistically stable across all malignancies. Forecast models suggest continued growth in incidence through 2030. In clinical cohorts, severe treatment-related toxicity was common. Advanced disease stage was associated with severe toxicity in osteosarcoma, while risk group was the primary determinant of hematologic toxicity in ALL. In neuroblastoma, toxicity was most pronounced among patients with high-risk disease receiving intensive chemotherapy.

Incidence of osteosarcoma and neuroblastoma is increasing in Kazakhstan while mortality remains stable. Despite stable survival, the burden associated with osteosarcoma, neuroblastoma, and acute lymphoblastic leukemia is increasing due to rising case numbers and substantial treatment-related toxicity.