The diagnosis of esophageal cancer is primarily based on symptoms. In the early stages, symptoms are generally nonspecific or only mild and typically do not attract the patient's attention. In the mid to late stages, the most common symptom is progressive difficulty swallowing. Additional diagnostic methods include esophageal radiography, MRI, and CT scans. Moreover, cytological diagnosis, endoscopic ultrasound of the esophagus, direct endoscopic examination and pathological sampling under endoscopy are utilized. The gold standard for confirmation still requires pathological or cytological diagnosis.