title: Gastric carcinoma presenting as double-channel pylorus on upper gastrointestinal series.
abstract: A double-channel pylorus or gastroduodenal fistula is a rare entity frequently acquired in association with penetrating peptic ulcer disease. The diagnosis is made by upper gastrointestinal series or by endoscopy. We report a 59-year-old man who presented with gastric outlet obstruction whose upper gastrointestinal series was typical of benign peptic ulcer disease demonstrating antral ulcers and a double-channel pylorus. At operation, gastric carcinoma infiltrating the pyloric channel and dividing it into two lumens was found. No gastroduodenal fistula was found. The "gastroduodenal fistula" on upper gastrointestinal series had been created by gastric carcinoma protruding into the pyloric channel and dividing the barium flow into two streams. One can no longer assume that a double-channel pylorus is due to benign ulcer disease.
mesh_terms: D000230:Adenocarcinoma / Q000000981:diagnostic imaging*; D003937:Diagnosis, Differential; D003951:Diagnostic Errors; D004378:Duodenal Diseases / Q000000981:diagnostic imaging; D005747:Gastric Fistula / Q000000981:diagnostic imaging; D006801:Humans; D007412:Intestinal Fistula / Q000000981:diagnostic imaging; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D011708:Pylorus / Q000002:abnormalities* / Q000000981:diagnostic imaging; D011859:Radiography; D013274:Stomach Neoplasms / Q000000981:diagnostic imaging* / Q000601:surgery; D013276:Stomach Ulcer / Q000601:surgery