SUMMARY Clinical data and histology from the oesophagus, gastric antrum, and duodenum were collected from 36 patients undergoing surgery for duodenal ulcer. Gastritis was present in 94% of the patients (25% of atrophic type), oesophagitis in 72% and duodenitis in 39%. Abnormal biopsies were present from all three sites in 33% of the patients. Only one patient showed three normal biopsies. The low incidence of duodenitis does not support the theory that duodenitis is part of the same spectrum as duodenal ulcer. Heartburn was related to the presence of gastritis (100%) and oesophagitis (76%) but not to duodenitis (52%). No relationship was found between the length of history, severity of pain, and histological abnormalities.The correlation of endoscopic appearances and histology of the upper gastrointestinal tract is well established,'13 but papers dealing with the relationship of symptoms and histology have either been inconclusive or shown no association. Fewer reports have correlated symptoms, the histology of oesophagus, stomach, and duodenum and their relationship to each other in biopsies taken simultaneously.8 9 The purpose of this study was to assess whether there was a correlation between the symptoms of duodenal ulceration, severe enough to require operation, and the microscopical appearances of the duodenum, antrum, and oesophagus in biopsies taken at the time of surgery during a truncal vagotomy and pyloroplasty. Methods PATIENTSThirty six patients were studied, 26 men and 10 women with a mean age of 43*5 years (range 19-71 years). All required surgery for duodenal ulcer, which had been diagnosed either radiologically or by endoscopy and confirmed at operation after being unsuccessfully treated medically; only one patient (no 11) was treated preoperatively with cimetidine, because the drug became available towards the end