Article History
Received: 17 April 2018
Accepted: 25 July 2018
First Online: 3 August 2018
Ethics approval and consent to participate
: This study obtained approval (Approval no. 2018-02-023) from the Samsung Medical Center institutional review board at Sungkyunkwan University School of Medicine to publish information obtained from public database. Informed consent from patients was waived by the Board.
: Not applicable.
: The authors declare that they have no competing interests.
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