Funding for this research was provided by:
National Research Foundation of Korea (2013R1A1A2A10008260, 2010-0010276)
National Cancer Center (0910220, 1210141)
Received: 22 November 2017
Accepted: 1 March 2018
First Online: 7 March 2018
Ethics approval and consent to participate
: All participants were given a detailed description of the study, and written informed consent was collected from all participants. The present study guidelines were approved by the Institutional Review Board of the National Cancer Center (IRB No. NCCNCS-10-350 and NCC 2015-0202).
: Not applicable.
: The authors declare no conflict of interest.
: Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.