Received: 13 March 2018
Accepted: 31 October 2018
First Online: 28 November 2018
Ethics approval and consent to participate
: This study was approved by the Institute Research Ethics Committee of the Sun Yat-Sen University Cancer Center, Guangzhou, China. Each patient provided signed, informed consent.
: Not applicable.
: The authors disclose no competing interests. There are no financial or non-financial competing interests (political, personal, religious, ideological, academic, intellectual, commercial or any other) to declare in relation to this manuscript.
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