Magnetically-guided capsule panendoscopy for gastrointestinal tumors (MagCam study)

Interventions: carcinoma of esophagus,gastric tumor, large intestine tumor Primary outcome(s): 1.Depiction ability of the capsule endoscope according to having magnetic induction or not for known gastrointestinal tumor 2.Depiction ability of the capsule endoscope according to the presence of the magnetic induction for the unknown lesion of the part unlike a known gastrointestinal tumor Study Design: randomized controlled trial, single blind, no treatment control/standard of care control, single assignment, diagnostic purpose