Guan, Xu
Wang, Yuliuming
Hu, Hanqing
Zhao, Zhixun
Jiang, Zheng
Liu, Zheng
Chen, Yinggang
Wang, Guiyu
Wang, Xishan
Article History
Received: 30 January 2018
Accepted: 23 April 2018
First Online: 1 June 2018
Ethics approval and consent to participate
: This study was approved by Institutional Review Board of National Cancer Center/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College and The Second Affiliated Hospital of Harbin Medical University. All methods were carried out in accordance with the Declaration of Helsinki and the approved guidelines. The data enrolled in this study were obtained from openly accessed SEER database and National Cancer Institute had given us permission to obtain data file for research only (Reference number: 10,249-Nov2015). The informed consent was not required according to personal identifying information was not included.
: The authors declare that they have no competing interests.
: Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.