Article History
Received: 30 December 2019
Accepted: 3 March 2020
First Online: 23 March 2020
Ethics approval and consent to participate
: This study was based on public use de-identified data from the SEER database and did not involve interaction with human subjects or use personal identifying information. The study did not require informed consent from the SEER registered cases and the authors obtained Limited-Use Data Agreements from SEER. No trial registration was necessary.
: Not applicable
: The authors declared that they have no competing interest. No third-party financial funds or materials were accepted or necessary for execution of this research project.