Funding for this research was provided by:
Eisai (not applicable)
Received: 25 January 2019
Accepted: 24 September 2019
First Online: 16 October 2019
Ethics approval and consent to participate
: The local ethics committee of the Kindai University Faculty of Medicine approved the study design and the protocol (approval number 26–143). The methods were carried out in accordance with the approved guidelines. Written informed consent was obtained.
: Written informed consent for publication of the results was obtained from all individual participants.
: The authors declare that they have no competing interests.