Funding for this research was provided by:
National Natural Science Foundation of China (81802619)
Text and Data Mining valid from 2020-02-14
Received: 30 November 2019
Accepted: 4 February 2020
First Online: 14 February 2020
Ethics approval and consent to participate
: The study was approved by the Ethics Committee of National Cancer Center/Cancer Hospital, Chinese Academy of Medical Sciences (Beijing, China). Written informed consent was obtained from all patients.
: Not applicable.
: The authors declare that they have no competing interests.