Funding for this research was provided by:
the Health and Medical Collaborative Innovation Project of Guangzhou City, China (201604020003)
National Natural Science Foundation of China (No. 81402532)
Received: 28 December 2017
Accepted: 20 December 2018
First Online: 8 January 2019
Ethics approval and consent to participate
: This study was conducted in compliance with institutional policy to protect patients’ private information, and was approved by the Institutional Review Board of Sun Yat-sen University Cancer Center. As the current study was a retrospective assessment of routine data, the ethics committee of our Cancer Center waived the need for individual informed consent.
: Not applicable.
: The authors declare no competing financial interests.
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