Received: 28 February 2021
Accepted: 28 September 2021
First Online: 12 October 2021
: The current study was approved by the Ethical Committee of Gunma University (Approval No. 1650), and written informed consent was obtained from all of the enrolled patients to use their tissues. It was performed in accordance with the principles of the Declaration of Helsinki.
: Not applicable.
: The authors declare no competing interests.