Article History
Received: 23 January 2018
Accepted: 12 March 2018
First Online: 5 April 2018
Compliance with ethical standards
:
: The authors declare that they have no conflict of interest
: This was a retrospective review of population level, aggregated, de-identified data from a national United States cancer database (NCDB). As a result, this study did not involve interaction with any human subjects or sensitive demographic or treatment data from any human subjects that could be tied to any particular patient or treatment center.
: For this type of study, formal consent is not required