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Article History

Received: 8 July 2021

Accepted: 20 January 2022

First Online: 25 February 2022

Declarations

:

: The data of this study comes from the SEER database. The SEER database is a tumor-related database developed by the National Cancer Institute of the United States, providing research data for researchers free of charge. All patients participating in the study received the ethical approval sought by the National Cancer Institute. The informed consent was obtained from all patients or, if patients are under 18, from a parent and/or legal guardian. The use of all data in the study follows the National Cancer Institute’s data use statement. The research content follows the statement of the National Cancer Institute guidelines.

: Not applicable.

: None.