1457pincidence, Mortality and Time Trends of Childhood Soft Tissue Sarcomas in Russia.

Methods: The analysis was based on annual reports of Ministry of Health and Federal State Statistics Service on cases, deaths and person-years by gender, age, calendar year and region. Age-specific and age-adjusted rates were calculated. Additionally, the average annual percent change (AAPC) with 95% confidence interval (95% CI), derived from a Poisson regression model, was estimated. Excess or deficit of incidence rates for geographical areas were expressed as standardized incidence ratio (SIR; standardized to rate of Russia as whole). Results: STS represent 5.8% of all childhood malignancies in Russia registered during for 2008-2012, behind leukaemias, brain tumors, lymphomas and renal tumors. The age-adjusted incidence rate (ASR, world standards) of STS per 1,000,000 patients below the age of 15 years was 7.2 (774 incident cases). The highest age-specific incidence was observed in children aged 0-4 years (11.5 per 1,000,000). A significant incidence trend was shown with AAPC of 3.7% [95% CI 3.2-4.2] between 1989 and 2012. The largest increase was observed in children aged 0-4 years (AAPC=5.6% [95% CI 4.76.5]. There were doubling of average Russian incidence rates in some areas such as Samarskaya oblast (about 15 cases per 1,000,000, SIR=2 [95% CI 1.3-2.8]. STS accounts for 10.8% of deaths from cancer in children in Russia and thus ranks third behind leukaemia and brain tumors. The age-adjusted mortality rate of STS per 1,000,000 patients below the age of 15 years for 2008-2012 was 4.3 (459 deaths). The highest age-specific incidence was observed in children aged 1-4 years (6.7 per 1,000,000). A significant increase of mortality between 1999 and 2012 was shown with AAPC of 3.2% [95% CI 1.84.7]). The geographical differences of death rates were not analysed because of small numbers.