The Diagnostic Value of Nitrogen Element (N) in Esophagus Cancer

Prior treatment

• Esophageal or gastric surgery
• History of previous upper abdominal surgery
• History of previous gastrectomy, endoscopic mucosal resection or endoscopic submucosal dissection
• History of previous neoadjuvant chemotherapy or radiotherapy
• Long-term Chinese medicine treatment of unknown drug nature

Other illness

• History of other malignant disease within past five years
• History of unstable angina or myocardial infarction within past six months
• History of cerebrovascular accident within past six months
• Requirement of simultaneous surgery for other disease
• Emergency surgery due to complication (bleeding, obstruction or perforation) caused by cancer
• Severe mental disorder

Lab values

• Unstable vital signs Coagulation dysfunction (INR\>1.5)
• Low peripheral blood platelet or using anti coagulation drugs

Other

• Pregnant women or breastfeeding
• Unwillingness or inability to consent for the study

• Esophageal cancer patients (Case): Subject diagnosed with ESCA based on typical clinical symptoms, endoscopic observation of esophageal lesions, and histopathological examination of biopsy specimens obtained from the lesion sites.
• Reflux esophagitis patients (Case control): Subject diagnosed diagnosed with reflux esophagitis based on typical clinical symptoms (e.g., heartburn and acid regurgitation) and endoscopic evidence of esophageal mucosal injury classified according to the Los Angeles classification system (Grade A: mucosal breaks ≤5 mm in length; Grade B: mucosal breaks \>5 mm in length but not confluent; Grade C: confluent mucosal breaks involving \<75% of the esophageal circumference; Grade D: confluent mucosal breaks involving ≥75% of the esophageal circumference).
• Health people: (Healthy control): no history of malignant tumors within the past five years, normal findings on gastroscopy, with no evidence of esophageal or gastric lesions, no history of gastrointestinal diseases such as gastroesophageal reflux disease (GERD) or Barrett's esophagus, blood counts, tumor biomarkers, and liver and kidney function tests within normal ranges.