Sun, Haiyan
Chen, Xi
Zhu, Tao
Liu, Nanfang
Yu, Aijun
Wang, Shihua
Article History
Received: 17 April 2018
Accepted: 7 June 2018
First Online: 29 June 2018
Ethics approval and consent to participate
: This study was exempt from review by the Medical Ethics Committee of Zhejiang Cancer Hospital due to the retrospective nature of the study and data being from a public database.
: Not applicable.
: The authors declare that they have no competing interests.
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