Received: 6 February 2022
Accepted: 25 July 2022
First Online: 9 August 2022
: All procedures were performed in accordance with the relevant guidelines. The present study was approved by the institutional review board of Okayama University Hospital (No. 2111–025). Informed consent was not required for this study because the data were already available to the public.
: Not applicable.
: The authors have no conflicts of interest to declare.