Text and Data Mining valid from 2019-06-11
Received: 30 January 2019
Accepted: 21 May 2019
First Online: 11 June 2019
Compliance with ethical standards
: This study was performed in accordance with the Helsinki standard and approved by the Ethical Review Board of the Shizuoka Cancer Center (30-J90-30-1-3S).
: The authors declare that they have no conflict of interest.