Funding for this research was provided by:
Lund University
Article History
Received: 9 May 2019
Accepted: 24 July 2019
First Online: 3 August 2019
Compliance with ethical standards
:
: The authors declare that they have no conflict of interest.
: This study was based on de-identified data from the SEER registry and did not involve interaction with human participants. The Ethics Committee for Clinical Research at Lund University, Sweden, approved the study protocol (2016/100).
: The authors obtained limited-use data agreements from SEER. Informed consent was waivered as this was a publicly available database using deidentified patient information.