Yang, D. Y. https://orcid.org/0000-0002-7047-1372
Wang, X.
Yuan, W. J.
Chen, Z. H. https://orcid.org/0000-0003-2059-4443
Article History
Received: 8 January 2019
Accepted: 14 March 2019
First Online: 23 March 2019
Compliance with ethical standards
:
: All the authors declare they have no conflict of interest.
: This article does not contain any studies with human participants or animals performed by any of the authors. It has been permitted to obtain the data from SEER database (Reference Number 14660-Nov2017).
: For this type of study, formal consent is not required.