Article History
Received: 16 August 2020
Accepted: 12 November 2020
First Online: 2 January 2021
Compliance with ethical standards
:
: This study was a single-center, retrospective study conducted in accordance with the principles of the Declaration of Helsinki (sixth revision 2013), with the approval of the Ethics Committee of the Japan Medical association Ethical Review Board, Tokyo, Japan.
: The authors have no conflicts of interest.