Cancer that develops within the tissues that line the esophagus is called esophageal cancer. The esophagus is the muscular tube that passes food from the throat into the stomach. Esophageal cancer growth is classified within four stages. In 3rd stage esophageal cancer, the cancer has already spread to the outer esophagus wall and may have already spread to nearby lymph nodes or tissues near the esophagus.
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