Received: 21 July 2020
Accepted: 20 January 2021
First Online: 30 January 2021
Ethics approval and consent to participate
: All patients consented to the institutional review board which allows comprehensive analysis of tumor specimens (Ethics committee of the Qingdao Municipal Hospital, Ref.: 2019 LSZ No.109).
: Not applicable.
: The authors declare that they have no competing interests.