Significance of screening by iodine staining of endoscopic examination in the area of high incidence of esophageal carcinoma

BACKGROUND & OBJECTIVE: In order to improve early detection and visualization of esophageal premalignant lesion and carcinoma, this study was designed to explore significance of the screening by iodine staining of endoscopic examination in the area of high incidence of esophageal carcinoma. METHODS: Three screenings were completed through endoscopic examination for 3164 persons in high-risk population. Esophageal epithelium was stained with iodine in endoscopic examination. According to mucosal color and pathological result, esophageal carcinoma and premalignant lesion were confirmed. RESULTS: After staining, the normal epithelium became brown and precancerous or malignant epithelium manifested yellow with sharp margin. (1) 100% early esophageal cancer was iodine staining positive, all lesions were grade I to grade II. The incidence rates of early esophageal carcinoma and advanced esophageal carcinoma were 1.60%-4.59% and 0.29%-1.09%, respectively. Early detection rate of esophageal carcinoma was all over 75%. (2) 95.6% severe dysplasia were staining positive; 91.3% lesion were grade I and grade II in staining. The incidence rate of severe dysplasia was 4.49%-7.68%. (3) 96.6% moderate dysplasia was positive in iodine staining, 73.3% lesion were grade II and grade III. (4) 92.3% mild dysplasia was positive in iodine staining; most of lesions were grade III. (5) 0.9% esophagitis and 0.4% normal esophageal mucosal were grade I and grade II in iodine staining, most of lesion were negative or grade III. CONCLUSION: The results demonstrated that the screening with endoscopic staining examination could improve early detection of esophageal carcinoma and precancerous lesion. Iodine staining showed highly sensitivity and specificity for identifying these precancerous and early squamous cancer lesions; it may be helpful for diagnosis of early esophageal carcinoma and precancerous lesion.