Received: 30 March 2020
Accepted: 20 July 2020
First Online: 23 July 2020
Ethics approval and consent to participate
: The study protocol was approved by the Ethical Review Board for Clinical Studies at Osaka University (control number 17255–2). The requirement of written informed consent was waived. All patients had the right to opt out of being included in research studies, and the procedure for doing so is written on the webpage of our Department.
: This study has no information by which an individual could be identified. Thus, the requirement for written consent for publication was waived.
: The authors declare no conflicts of interest in association with the present study.