Are acid secretory tests of diagnostic value in patients with benign-looking gastric ulcers?

In 41 patients in whom endoscopy showed benign gastric ulcer, gastric secretory function was assessed before and after stimulation with pentagastrin (6 micrograms/kg); they were then followed up for a period of 2-4 years. Of these 41 patients, 37 had benign and the remaining 4 malignant ulcers. Of the 37 patients with benign gastric ulcers, 11 had basal achlorhydria but all secreted acid after pentagastrin stimulation. Seven of these 37 patients (19%) secreted less than 5 mmol/h in response to stimulation with pentagastrin. Of the 4 patients with malignant gastric ulcer, 3 had basal achlorhydria. After pentagastrin stimulation 3 of these patients (75%) secreted up to 5 mmol/h and 1 patient secreted 17 mmol/h. Biopsy evidence of malignancy was only obtained after repeat endoscopy and biopsy in 2 of these 4 patients. The present study confirms that a malignant ulcer may simulate a benign ulcer on endoscopy, and shows that the finding of hypochlorhydria in such patients warrants a cautious approach with repeat endoscopy and biopsy to exclude a malignant lesion.