Funding for this research was provided by:
Program for Outstanding Medical Academic Leader, Central University Cross Fund and Chinese Medical Association Fund (22120170145)
Text and Data Mining valid from 2019-04-30
Received: 3 September 2018
Accepted: 11 April 2019
First Online: 30 April 2019
Ethics approval and consent to participate
: The data used in this study were based on Surveillance, Epidemiology and End Results (SEER) Database, provided by National Cancer Institute of United Sates. Protocols used in this database were approved by the Ethics Committee of National Cancer Institute’s Surveillance, Epidemiology and End Results (SEER) Database.
: Not applicable.
: The authors declare that they have no competing interests.
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