The incidence rate of esophageal cancer is the eighth of all malignant tumors in the world, and the incidence rate is especially high in developing countries. China is also a country with high incidence of esophageal cancer, and the survey in the 1990s showed that the mortality rate of esophageal cancer was the fourth of all malignant tumors, and the incidence rate of men was significantly higher than that of women, and the high incidence age group was 60-64 years old.
Squamous carcinoma is the most common in high incidence areas of esophageal cancer, while adenocarcinoma is common in non-high incidence areas. Squamous carcinoma is mostly found in men and is related to smoking and alcohol abuse; adenocarcinoma is related to Barrett’s esophagus, gastroesophageal reflux and esophageal hiatal hernia. Recently, the incidence of squamous esophageal cancer in the United States and European countries has gradually decreased, accounting for less than 30% of all esophageal cancers.
I. Diagnostic points
(I) Clinical manifestations
1.Symptoms
(1) In the early stage, there are often burning sensation, rubbing sensation, pins and needles sensation, slow passage or stagnation of physical objects behind the sternum.
(2) Progressive dysphagia is the manifestation in the middle and late stages, often accompanied by vomiting mucus when there are choking symptoms.
(3) Pain behind the sternum and back.
(4) Hoarseness is often produced by pressure on the recurrent laryngeal nerve.
(5) Choking and coughing may occur in case of esophagotracheal fistula.
2.Signs
Esophageal cancer mostly has no specific physical signs, especially in early stage patients. Some patients in the middle and late stages may become dehydrated and malnourished due to long-term difficulty in eating.
(II) Examination means
1.Esophageal X-ray barium meal examination is better than CT and MRI for early esophageal cancer, especially for lesions confined to mucous membrane layer.
2.Endoscopy Cytological smear or biopsy is feasible at the same time of endoscopy. In recent years, endoscopic iodine staining technology has obviously improved the detection rate of early esophageal cancer.
3.Ultrasound endoscopy can determine the depth of tumor infiltration and abnormal lymph nodes outside the duct wall, etc.
4.CT can show the thickness, shape, tumor invasion and relationship with mediastinal organs of the canal wall.
5.Esophageal mesh shedding cytology examination is convenient and easy to perform, and is an important tool for screening and outpatient examination.
(III) Pathological classification
1.Early stage esophageal cancer is divided into occult type, erosion type, plaque type and papillary type.
2.Late stage esophageal cancer is divided into medullary type, myxomatous type, ulcerative type and narrowing type, with medullary type being the most common.
3.Histological classification: squamous carcinoma, adenocarcinoma, small cell undifferentiated carcinoma and carcinosarcoma, squamous carcinoma is the most common, accounting for more than 90%, while adenocarcinoma accounts for about 5%.
Treatment principles
Patients with carcinoma in situ can choose endoscopic mucosal resection (EMR) or ablation therapy; for Tla patients, EMR followed by ablation therapy or direct esophagectomy as for Tlb patients without lymph node metastasis; patients with Tlb with lymph node metastasis or T2~T4a (with or without lymph node metastasis) can consider preoperative radiotherapy (non-neck segment) and then surgery, or perioperative chemotherapy plus surgery (for adenocarcinoma). For patients who do not want to undergo surgery, radical radiotherapy (radiotherapy 50-50.4 Gy) is considered. For patients with low-risk, less than 2 cm, well-differentiated non-cervical segment, esophagectomy is considered; for patients with T4b, radical radiotherapy is given, but only palliative chemotherapy is given if the trachea, large vessels or heart are invaded.
For patients who underwent R0 resection and had no lymph node metastasis, if the case was squamous carcinoma, it could be observed only. If the case is adenocarcinoma, then: (i) T1 stage patients who have no clear evidence of recurrence are followed up only without radiotherapy or chemotherapy. ②T2N0 patients should also be selectively treated with radiotherapy if they are hypofractionated adenocarcinoma (or high G grade), by lymphovascular infiltration, peripheral nerve infiltration or age <50 years; the rest of T2N0 patients can be followed up. (iii) Patients with T3N0 or higher stage should receive fluorouracil-based radiotherapy.
For patients with positive lymph nodes after R0 resection, if the pathology is squamous carcinoma, they can be observed. If adenocarcinoma is present, then: ①Patients with adenocarcinoma of the distal esophagus or gastroesophageal junction should be given postoperative radiotherapy. ② Proximal or middle esophageal adenocarcinoma can be closely followed and postoperative radiotherapy can also be used.
Patients with R1 resection (i.e. tumor visible under the microscope at the margin) should be given radiotherapy plus fluorouracil/cisplatin-based chemotherapy. Patients who have undergone R2 resection (i.e., tumor visible to the naked eye at the margins or Mlb) should be given radiotherapy and inappropriate treatment according to the extent of tumor spread.
Patients who cannot tolerate radiotherapy and cannot be surgically resected are given best supportive care.