Detecting early esophageal cancers, with special reference to the intraepithelial stage.

Early-stage esophageal cancers, particularly intraepithelial cancers, are extremely difficult to detect because patients have no particular complaints and x-ray is so often useless. Only panendoscopic examination has proved highly effective in discerning lesions. Lugol-combined panendoscopic examination is not only feasible, but also effective in spotting the presence and spread of lesions.