Funding for this research was provided by:
Received: 19 June 2018
Accepted: 8 August 2018
First Online: 16 August 2018
Ethics approval and consent to participate
: This study was approved by institutional review boards in Shizuoka Cancer Center and Toyama University (approval number: Shizuoka Cancer Center, T23–3; Toyama University, 22–96). Written informed consent to participate in the study was obtained from each study participant in Toyama University. However, the need for individual informed consent to participate in the study has been waived by institutional review boards in Shizuoka Cancer Center (approval number: Shizuoka Cancer Center, T23–3), as this study was retrospective exploratory research.
: Not applicable.
: The authors declare that they have no competing interests.
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