[30-year experiences on early detection and treatment of esophageal cancer in high risk areas].

The author had conducted the clinical study on early diagnosis and early therapy of esophageal cancer (EC) in the area of high prevalence for more than 30 years. In the endoscopic survey, 742 patients were diagnosed as early EC from 22,285 participants. The endoscopic appearance of the mucosa in early EC was classified into three types: (1) change of mucosa color: red and white area; (2) Increased thickness and change of the vascular pattern of the mucosa; (3) mucosa morphology: erosion, plaque, coarseness and nodular. Iodine staining under endoscopic examination had promoted the early detection of EC and precancerous lesions. Since 307 patients with EC at early stage (65 carcinoma in situ, 95 intramucosal carcinoma, and 147 submucosal carcinoma) had undergone esophagectomy. There were no lymphatic metastasis in carcinoma in situ, however there were 2 cases (2.11%) of intramucosal carcinoma and 27 cases (18.37%) of submucosal carcinoma with lymph node metastasis. 24-year follow-up, results showed that 5-year survival rate is 84.1% and a 10-year survival rate is 72.9% among the cases of esophagectomy. A 5-year survival rate is 100% in 22 cases followed up for full five years among 141 cases with endoscopic mucosectomy. According to this study, severe dysplasia and some moderate dysplasia were precancerous lesions. Should these precancerous cases be treated, the cancerization risk of target population would reduce dramatically and the incidence of EC would be decreased down to 2/3.