Gastrointestinal cancer

Gastrointestinal cancer refers to malignant conditions of the gastrointestinal tract (GI tract) and accessory organs of digestion, including the esophagus, stomach, biliary system, pancreas, small intestine, large intestine, rectum 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 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.

Worldwide, the incidence of each type is about the same, but in developed countries like North America and Europe adenocarcinoma is the more common.

[6] Important factors that may contribute to the development of gastric cancer include diet, smoking and alcohol consumption, genetic aspects (including a number of heritable syndromes) and infections (for example, Helicobacter pylori or Epstein-Barr virus) and pernicious anemia.

[2] Early pancreatic cancer does not tend to result in any symptoms, but when a tumor is advanced, a patient may experience severe pain in the upper abdomen, possibly radiating to the back.

[10] People get liver cancer (also called hepatocellular carcinoma, HCC or hepatoma) typically from a prolonged Hepatitis B or C infection or as a result of cirrhosis from chronic alcoholism.

Liver cancer may bring about yellowing of the skin and eyes (jaundice), itching (pruritus), or cause a buildup of fluid in the abdomen (ascites).

A person may feel an enlarging mass, or the cancer might be revealed by abnormal liver function tests.

It typically originates in the secretory cells lining the gut, and risk factors include diets low in vegetable fibre and high in fat.

Anal cancer is strongly associated with ulcerative colitis and the sexually transmissible infections HPV and HIV.

Anal cancer may be a cause of constipation or tenesmus, or may be felt as a palpable mass, although it may occasionally present as an ulcerative form.

[15]: 580 A gastrointestinal carcinoid tumor is a rare, slow-growing form of cancer that affects certain cells in the lining of the stomach and intestines.

The cells it affects make hormones that regulate the production of digestive juices and muscles that move food through the stomach and intestines.

Barrett's esophagus is the dominant pre-malignant lesion of esophageal adenocarcinoma,[18] and has prevalent epigenetic alterations.

Luo et al.[26] summarized the substantial body of evidence that field cancerization occurs in the colon, often due to aberrant DNA methylation.

High bile acid exposure has been implicated in several cancers of both the upper and lower digestive tract.

Squamous cell cancer, upper oesophagus.
Age-standardised death rates from esophageal cancer, as reported by the WHO in 2004. [ 3 ]
Salivary glands Parotid gland Submandibular gland Sublingual gland pharynx Tongue Esophagus Pancreas Stomach Pancreatic duct Ileum Anus Rectum Vermiform appendix Cecum Descending colon Ascending colon Transverse colon Colon (anatomy) Bile duct Duodenum Gallbladder Liver oral cavity
Upper and lower human gastrointestinal tract
Example of an invasive colorectal cancer .
Longitudinally opened freshly resected colon segment showing a cancer and four polyps. Plus a schematic diagram indicating a likely field defect (a region of tissue that precedes and predisposes to the development of cancer) in this colon segment. The diagram indicates sub-clones and sub-sub-clones that were precursors to the tumors.