Department of Internal Medicine;
Chung-Ang University College of Medicine;
Heukseok-dong;
Dongjak-gu;
Seoul 156-755;
South Korea;
Department of Pathology;
Green Cross Reference Laboratory;
314 Pojung-dong;
Giheung-gu;
Yongin-si;
Kyunggi-do 446-913;
South Korea;
Gastric; cancer; National; Cancer; Screening; Program; Opportunistic; screening; Early; gastric; cancer;