Funding for this research was provided by:
Chinese Anti-Cancer Association (CSNO2014MSD01)
Article History
Received: 18 January 2017
Revised: 1 September 2017
Accepted: 6 September 2017
First Online: 16 September 2017
Compliance with ethical standards
:
: The authors declare that they have no conflicts of interest.
: Because this study is a systematic review and does not involve original data, ethical approval was not required.
: Because this study is a systematic review and does not involve original data, informed consent is not applicable.