Gastrointestinal cancer

Gastrointestinal cancer refers to malignant conditions of the gastrointestinal tract, including the esophagus, stomach, biliary system, pancreas, bowels, and anus. The symptoms relate to the organ affected, and can include obstruction (leading to difficulty swallowing or defecating), abnormal bleeding, or other associated problems. The diagnosis often requires endoscopy, followed by biopsy of suspicious tissue. The treatment depends on the location of the tumor, as well as the type of cancer cell and whether it has invaded other tissues or spread elsewhere in the body. This also determines the prognosis.

Types
Types of gastrointestinal cancer include:
 * Esophageal cancer
 * Stomach cancer (also called gastric cancer)
 * liver cancer (also called hepatocellular carcinoma, HCC, and hepatoma)
 * Gallbladder cancer
 * Pancreatic cancer
 * Colorectal cancer (also called colon cancer, bowel cancer, and rectal cancer)
 * Anal cancer
 * Gastrointestinal stromal tumors (GIST)

Prognosis
Prognosis is variable, and depends almost entirely on the specific type of cancer. Esophageal cancer has a dismal prognosis because it is often detected late; colon cancer has a comparatively good prognosis when detected early. Pancreatic cancer also has a very poor prognosis, with only 5% of patients surviving more than 5 years after diagnosis.