Received: 31 July 2020
Accepted: 15 July 2021
First Online: 6 August 2021
: The current study was designed and conducted according to the principles outlined in the Declaration of Helsinki and within the guidelines of Good Clinical Practices and was approved by the Institutional Review Board of Gunma University. The need for written informed consent was waived because of the retrospective observational nature of this study, but all the patients in the study had the opportunity to opt-out.
: Not applicable.
: KS has received research grants from Takeda and Astellas outside of this work.