Funding for this research was provided by:
National Cancer Institute (U01 CA195564, U01 CA195564)
Received: 6 July 2017
Accepted: 19 September 2017
First Online: 21 November 2017
Ethics approval and consent to participate
: In this retrospective study, all patient data were Health Insurance Portability and Accountability Act-compliant and acquired under institutional review board approval that waived the need for informed consent.
: Not applicable.
: The authors declare that they have no competing interests.
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