Funding for this research was provided by:
Japan Society for the Promotion of Science (KAKENHI #18K08170)
Takeda Science Foundation
Received: 15 April 2019
Accepted: 28 June 2019
First Online: 5 July 2019
Ethics approval and consent to participate
: This study was approved by the Institutional Review Board of the University of Tokyo (the approval number 14–71). Because this was a retrospective observational study and included no therapeutic intervention, written informed consent was waived.
: Consent to publish was obtained from the person with the chest X-ray shown in Fig. InternalRef removed.
: The authors declare that they have no competing interests.