Received: 16 January 2021
Accepted: 10 June 2021
First Online: 2 July 2021
: The research protocol was approved by the ethics committee of Peking University International Hospital (2021–001(BMR)), and it was conducted in accordance with the 1964 Declaration of Helsinki and its later amendments. The need for written informed consent was waived owing to the retrospective nature of the study.
: Not applicable.
: The authors declare that they have no competing interests.