Shang, Xiaoling
Liu, Jia
Li, Zhenxiang
Lin, Jiamao
Wang, Haiyong
Article History
Received: 4 December 2018
Accepted: 5 June 2019
First Online: 17 June 2019
Ethics approval and consent to participate
: We were approved by the National Cancer Institute to use patient data from the SEER database. Participants consent was not necessary because the study involved using a previously published identity database based on the SEER database.
: Not applicable.
: The authors declare that they have no competing interests.