Funding for this research was provided by:
China Postdoctoral Science Foundation (2016M590640)
Key Technologies Research and Development Program (2018YFC1313201)
Key Technology Research and Development Program of Shandong (2016CYJS01A03)
Postdoctoral Innovation of Shandong Province (201501010 and 201601006)
Text and Data Mining valid from 2019-10-22
Received: 22 June 2019
Accepted: 25 September 2019
First Online: 22 October 2019
Ethics approval and consent to participate
: This study was approved by the Institutional Review Board of Shandong Cancer Hospital (no SDTHEC201801007). For this retrospective study, formal written informed consent from all patients was not required, and all data were kept confidential.
: Not applicable.
: The authors declare that they have no competing interests.