Funding for this research was provided by:
Olympus Korea (4-2018-1162)
Received: 2 March 2020
Accepted: 7 July 2020
First Online: 14 July 2020
Ethics approval and consent to participate
: The authors follow either the Declaration of Helsinki to protect the patients, and the trial will be performed according to the ICH-GCP guidelines. Before enrollment of first patient, this study was approved from the institutional review boards of all research centers (5 tertiary hospitals) in South Korea, including Yonsei Cancer Center (4–2018-1162), Seoul National University Hospital, St. Vincent’s Hospital, Kyungpook National University Chilgok Hospital, and Korea University Anam Hospital. All patients will understand and agree to the aims and process of the trial, possible results and risks. An informed consent has to be written in the language which patients can understand, and be explained by an investigator. If patients cannot read an informed consent, an investigator has to read it in the presence of a witness. Although a patient signed an informed consent at first, an investigator has to stop a process of the patient when he or she refuses. A copy of signed informed consent should be provided to the patient. An original copy will be an investigator’s safekeeping.
: Consent was signed by the patient for all the images.
: The authors declare that they have no competing interests.