Malignancy is the most common cause of gastric outlet obstruction in the era of H2 blockers.

OBJECTIVES: To determine the relative incidence of malignant and nonmalignant pathology in patients presenting with gastric outlet obstruction in the era of H2 blockers and to determine whether clinical features can differentiate between the two causes.
METHODS: The charts of 33 consecutive patients with gastric outlet obstruction admitted to one institution between July 1990 and November 1993 were reviewed to determine etiology, management, and outcome. The diagnosis of gastric outlet obstruction was based on clinical presentation, an upper gastrointestinal barium study, and/or an inability during upper endoscopy to intubate the second portion of the duodenum. Patients with gastroparesis or a previously known cancer were excluded.
RESULTS: Sixty-one percent (20 patients) had malignancy as the cause of their gastric outlet obstruction. Thirty-nine percent (13 patients) had benign disease. The patients with cancer tended to be older, and fewer had a history of peptic ulcer disease, although these factors were not statistically significant. The use of nonsteroidal anti-inflammatory drugs was not associated with gastric outlet obstruction. Four patients had malignancy that had not been suspected before operation despite numerous endoscopic and radiological studies.
CONCLUSION: The incidence of malignancy in patients presenting with gastric outlet obstruction is greater than 50%. The etiology of gastric outlet obstruction cannot be predicted by age, history of peptic ulcer disease, or nonsteroidal anti-inflammatory drug use. The endoscopic treatment of gastric outlet obstruction should be approached with caution because malignancy cannot be reliably excluded by endoscopic or radiological studies.