1. Enrollment:407 subjects.
2. The inclusion criteria of this study: subjects who have participated in Phase III clinical trials.Phase III clinical trial（NCT02787239） has ended.
3. The exclusion criteria: ①Subjects died; ②Subjects are unwilling to participate in follow-up study; ③ the investigator judges that the subject is not suitable for participating the study.
4. Duration and method of follow-up: 2-10 years (2020-2027)after the end of the Phase III trial and follow up the subjects by the phone.
5. Statistical analysis method: For progression-free survival and overall survival (OS), the median time and its 95% confidence intervals will be calculated by the Kaplan-Meier method.The Log-Rank test will be used for finding the difference between groups. The efficacy will be analyzed by SAS9.4 , and all hypothesis tests are two-sided. The confidence level of all confidence intervals is 95%. P value less than 0.05 was regarded as statistically significant.
