Esophageal cancer begins in the esophagus—the tube that carries food and liquids from the throat to the stomach. Most cases are one of two types. Squamous cell carcinoma starts in the flat cells that line the upper and middle parts of the esophagus. Adenocarcinoma develops from gland-like cells, usually in the lower esophagus near the stomach, often in the setting of long-term reflux and Barrett’s esophagus. Knowing the type matters because it influences tests, treatment choices, and expected side effects.