Received: 1 February 2021
Accepted: 22 March 2021
First Online: 22 May 2021
: The study protocol was approved by the Animal Experiment Committee in National Cancer Center Japan, and all animal experiments were conducted in accordance with the relevant guidelines and recommendations pertaining to research on animals (K18-024, 2018/12/27).
: Not applicable.
: TY received grants for this study from HOYA Pentax Medical Japan. HS, YY, NT, HH, KT, TK, TF, TA, and SF declare no potential competing interests.