Results
The 5y-EFS and 8y-EFS of the whole cohort in the 10 years were 68.7±2.1% and 67.6±2.2%; the 5y-OS and 8y-OS were 81.9±1.9% and 81.2±2.1%. Our risk stratification system was updated twice during the 10 years, forming three periods. The percentage of very low risk (VLR) cohort who accepting only surgery without chemotherapy was increased in 2016-2018 period than the 2010-2015 period and 2008-2009 period. While the 3y-EFS of the three periods were similar (P=0.961). The outcome in VLR and low risk (LR) patients were excellent with 8y-EFS around 92% (VLR=93.0±2.8%, LR= 92.1±1.8%). The outcome in high risk (HR) patients was significantly poorer with 8y-EFS only as 16.6±4.1% even than intermediate risk (IR) patients with 8y-EFS as 69.6±4.4% (P<0.001).