Esophageal cancer is a malignant tumor occurring in the epithelial tissue of esophagus, accounting for about 3% of all malignant tumors, and is one of the common malignant tumors in human beings. China is a high incidence area of esophageal cancer, and the incidence age is mostly above 40 years old, and more men than women. The occurrence of esophageal cancer is related to the chronic stimulation of nitrosamines, inflammation and trauma, genetic factors and the content of trace elements in drinking water, food and vegetables.
I. Clinical symptoms of esophageal cancer
Early esophageal cancer has no specific symptom, and swallowing difficulty appears only when there is obvious narrowing. Most patients do not pay attention to it and delay the disease. Therefore, early detection and early treatment is the key.
1.Common manifestations in early stage.
(1) Dryness and tightness in the throat, especially when swallowing dry and rough food.
(2) Food retention or foreign body sensation, when swallowing food or drinking water, there is a feeling of slow downward movement of food and stagnation.
3）There is a feeling of tightness and stuffiness behind the sternum and a feeling of choking in the throat. When swallowing food, there is pain behind the sternum or under the raphe, which may be burning, pinching or pulling, rubbing-like pain, and it is more prominent when swallowing rough, burning or irritating food.
2.Middle stage
1) Typical symptoms are progressive dysphagia, first it is difficult to swallow dry food, followed by semi-liquid, and finally water and saliva cannot be swallowed.
2)Often spitting mucus-like sputum, which is the secretion of saliva and esophagus from the lower throat.
3)Gradual wasting, dehydration and weakness. Persistent chest pain or back pain is indicated as an advanced symptom.
3.Concomitant symptoms
1)Hoarseness. Invasion or compression of the laryngeal nerve by cancer or lymph nodes may cause paralysis of the vocal cords, resulting in hoarseness.
2) Neck and/or supraclavicular mass, which is the more common site of lymph node metastasis in esophageal cancer.
3) Invasion of phrenic nerve may cause erratic or phrenic nerve palsy; compression of trachea or bronchus may cause shortness of breath and dry cough; erosion of aorta may produce fatal bleeding.
4) If the cancer is located in the upper esophagus or complicated with esophage-trachea or esophage-bronchial fistula, cervical sympathetic nerve palsy syndrome can be produced when swallowing liquid.
Early examination of esophageal cancer
1.Esophageal exfoliative cytology examination: it is the first choice for early diagnosis of esophageal cancer, and it has been proved through practice that it is feasible to conduct large area census in high incidence area of esophageal cancer, and the total positive rate can reach more than 90%, which is simple, less painful and with low false positive rate.
2.Barium X-ray imaging: this method can detect the changes of esophageal mucosa, structure and function at an early stage, which can help to judge the precancerous lesions of esophagus at an earlier stage.
3.Fiber endoscopy: It has become a reliable method for routine clinical diagnosis, postoperative follow-up and efficacy observation of upper gastrointestinal diseases (esophageal cancer, gastric cancer, etc.). In early esophageal cancer, the detection rate of fiberoptic endoscopy can reach more than 85%.
4.CT scan of the chest: it is helpful for staging of esophageal cancer, judgment of possible resection and estimation of prognosis.