Obstructive sensation or dull pain behind the sternum when swallowing dry food is one of the early and middle stage manifestations of esophageal cancer. It is mainly progressive dysphagia, and in the early stage, there may be only discomfort or blockage feeling when swallowing, pain behind the sternum or discomfort behind the sternum when swallowing food. China is a high incidence area of esophageal cancer, and nearly 150,000 people die from this disease every year nationwide, and the second highest number of deaths due to esophageal cancer after stomach cancer. In the examination of esophageal cancer, using esophageal X-ray imaging, the swallowing function of the pharynx of the upper esophageal port and the cardia of the lower esophagus, lesions inside and outside the lumen of the esophagus, axial changes of esophageal imaging, differentiation of benign and malignant tumors and estimation of possible resection of esophageal cancer can be examined. Examination methods for obstruction or dull pain behind the sternum when swallowing dry food: 1. Tumor markers: No such markers with certain accuracy have been found for esophageal squamous carcinoma. The most sensitive immunomarker, squamous cell carcinoma-associated antigen (SCC-RA), is often negative in benign esophageal tumors, while the seropositivity rate in patients with esophageal cancer is 40% to 52%, and increases with further invasion of lesions, lymph node metastasis, late stage of disease, and increase in tumor size, but unfortunately, it is rarely positive in early-stage cancer and negative in any stage of poorly differentiated cancer. Another immunological index is the epidermal growth factor (EGF) receptor. 2.X-ray examination: It is an important diagnostic tool for the early diagnosis of esophageal cancer. Since the lesions of early esophageal cancer are mostly confined to the mucosal layer, it is difficult to identify such subtle lesions on X-ray, but careful observation of the changes of esophageal mucosal folds and the lumen diastasis is important to confirm early esophageal cancer; supplemented by fiberoptic esophagoscopy or gastroscopy combined with cytological examination, it is helpful to improve the diagnosis rate of early esophageal cancer. In early stage esophageal cancer, it is not easy to show the lesions, so it is necessary to adjust the barium meal during the examination, make the patient swallow in small bites and observe carefully in multiple axes in order not to miss the diagnosis. The typical X-ray signs such as obvious filling defect can be found in the barium meal examination of esophageal X-ray in middle and late stage esophageal cancer.