Definition:
stage 0 esophageal carcinoma in situ (... ee-SAH-fuh-JEE-ul KAR-sih-NOH-muh in SY-too)
Cancer has formed in the inner lining of the esophagus wall. Stage 0 is also called high-grade dysplasia.
Enlarge Stage 0 adenocarcinoma of the esophagus; drawing shows the esophagus and stomach. An inset shows cancer cells in the inner lining of the esophagus wall. Also shown are the mucosa layer, thin muscle layer, submucosa layer, thick muscle layer, and connective tissue layer of the esophagus wall. The lymph nodes are also shown.

Stage 0 adenocarcinoma of the esophagus. Cancer has formed in the inner lining of the esophagus wall.