Gastric outlet obstruction (GOO) is a clinical syndrome characterized by epigastric abdominal pain and postprandial vomiting due to mechanical obstruction. The term gastric outlet obstruction is a misnomer since many cases are not due to isolated gastric pathology, but rather involve duodenal or extraluminal disease. This topic will review the evaluation of adults with GOO. Endoscopic methods to treat GOO are discussed in detail separately. (See "Enteral stents for the palliation of malignant gastroduodenal obstruction".)

Symptoms and Signs
• History of symptomatic peptic ulcer disease
• Increasing ulcer pain with anorexia, vomiting of undigested food, and failure to gain relief from antacids
• Absence of bile pigment in vomitus reflects level of duodenal obstruction
• Weight loss, dehydration, and malnutrition may be marked
• Peristalsis of the distended stomach may be visible
• Upper abdominal distention and tenderness are usually apparent
• Tetany with advanced alkalosis

EPIDEMIOLOGY

Precise estimates on the incidence of GOO are lacking. In 1990, as many as 2000 operations for GOO were performed annually in the United States . It is likely to have declined in recent years because of the decline in peptic ulcer disease, which has historically been an important cause of GOO.

ETIOLOGY

The etiology of GOO has changed over the past several decades. Benign disease was responsible for the majority of cases of GOO in adults until the late 1970s, of which peptic ulcer disease accounted for up to 90 percent of cases. With the decline in peptic ulcer disease, it is estimated that 50 to 80 percent of all cases of GOO are attributable to malignancy.

Gastric outlet obstruction

Any disease that mechanically impedes gastric emptying, the normal emptying of the stomach. There is obstruction of the channel of the pylorus and duodenum through which the stomach empties. The cause of the obstruction may be a benign or malignant disease. The most common malignancy that produces gastric outflow obstruction is pancreatic cancer. The benign causes of gastric outflow obstruction include pyloric ulcer and gastric polyps in adults, pyloric stenosis and congenital duodenal webs in children, and the ingestion of caustic substances in all age ranges. Gastric outlet obstruction may be abbreviated GOO.

Neoplastic
Malignant-Pancreatic adenocarcinoma with extension to the duodenum or stomach is a common cause of malignant GOO . Fifteen to 25 percent of patients with pancreatic cancer present with GOO. Such patients also commonly have biliary obstruction.  

Distal gastric cancer remains a relatively common cause of malignant GOO, accounting for up to 35 percent of GOO. However, the absolute number of cases has probably declined because of the decreased incidence of gastric cancer in developed nations and the increase in the proportion of gastric cancers arising from a proximal location.

Clinical Gastroenterology Journal (formerly Journal of Colitis & Diverticulitis) is a peer reviewed, open access journal considering research on all aspects of digestive system, gastrointestinal diseases, liver, bilary tract, pancreas, diseases of related organs Ulcer medicine, Colitis, Diverticulitis and associated disorders and their treatment. The Journal aims to provide a platform for the exchange of scientific information addressing clinical research and practice of Gastroenterology and Hepatology.

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