AbstractA fifty-five year old male with an appendicular abscess had 100 ml of pus drained from the right lower quadrant. Two months later, an interval appendectomy was performed. The macroscopically normal appendix had a portion of fibroadipose mesoappendix attached. Microscopic evaluation using routine stains showed redundance and diverticular extrusion as well as foci of ectopic gastric glands. Immunohistological studies for detection of gastrin immunoreactivity revealed gastrin containing cells in foci of ectopicgastric glands. This represents the first report in which gastrin was demonstrated in an appendix, confirming the presence of heterotopic gastric mucosa.