1. National Cancer Control Institute, National Cancer Center, Goyang, Korea
2. Lung Cancer Clinic, Severance Hospital, Yonsei University Health System, Seoul, Korea
3. Department of Laboratory Medicine, Center for Diagnostic Oncology, National Cancer Center Hospital, National Cancer Center, Goyang, Korea
4. Center for Colorectal Cancer, National Cancer Center Hospital, National Cancer Center, Goyang, Korea
5. Center for Cancer Prevention & Detection, National Cancer Center Hospital, National Cancer Center, Goyang, Korea
6. Department of Laboratory Medicine and Genetics, Soonchunhyang University Bucheon Hospital, Soonchunhyang University College of Medicine, Bucheon, Korea
7. Department of Gastroenterology, Hanyang University Guri Hospital, Guri, Korea