Endoscopic examination. Esophageal cancer was observed at the middle to distal esophagus. It spanned more than three-fourths of the luminal circumference. (A) White light endoscopy. (B) Chemoendoscopy with iodine staining. After chemoradiotherapy, the lesion size decreased to approximately half of the circumference of the esophageal lumen. (C) White light endoscopy. (D) Chemoendoscopy with iodine staining.