Received: 23 July 2020
Accepted: 7 October 2020
First Online: 15 October 2020
Ethics approval and consent to participate
: All analyses of human data conducted in this study were approved by the Institutional Review Board of The Lishui people’s hospital and in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards. Informed consent was exempted because of the retrospective nature of this study. All authors signed authorization forms and received permission from SEER to access and use the dataset.
: Not applicable.
: The authors declare that they have no competing interests.