·From October 2012 to January 2020, 52 AT/RT children treated in Xinhua Hospital, Shanghai Jiao Tong University School of Medicine were selected. Their clinical data and follow-up were recorded and their 3-year progression-free survival (PFS) and 3-year overall survival (OS) were analyzed by Kaplan-Meier method. According to the age of the children, they were divided into ≥3-year-old group and <3-year-old group. The clinical characteristics and survival status of the two groups were compared. Univariate and multivariate Cox proportional hazards regression models were used to analyze the impact of clinical characteristics on overall survival. The significance of immunohistochemical indicators in children with different survival outcomes was explored.

·There were 34 males and 18 females in AT/RT children, 65.4% of which were younger than 3 years old, and the average age of onset was (35.2±28.2) months. The median survival time was 7.7 months, and 3-year PFS and 3-year OS was (29.3±7.6)% and (30.4±7.6)%, respectively. There were significant differences between the two groups in receiving radiotherapy and chemotherapy, serious complications, 3-year PFS and 3-year OS (all P<0.05). Univariate Cox regression analysis showed that the survival risk of children, who was less than 3 years old and underwent primary tumor invading the spinal canal, tumor metastasis, and partial resection, without radiotherapy or chemotherapy, was increasing (all P<0.05). Multivariate Cox regression analysis showed that tumor metastasis was an independent risk factor for overall survival of children (P=0.024). The results from immunohistochemistry showed that the positive expression of SYN in survival children was significantly higher than that in dead children (P=0.003).

·Children younger than 3 years old with AT/RT have more severe complications and lower overall survival rate, so it is necessary to implement more accurate therapeutic stratification and diversified treatment methods.