ZSCAN18 and esophageal cancer: Most prior studies have focused on malignant tumors of the digestive tract, including cancers of the esophagus, stomach, pancreas, colon, rectum, bile duct, and liver, which found that ZSCAN18 methylation was common and negatively correlated with expression profiles, indicating the potential of ZSCAN18 methylation as a prognostic biomarker (8, 10–13, 29).