G-cell density in the antral mucosa: a feasibility study C.PESCE, R.ROSSI, E.LENTI & R.TANZI Cattedra di Istituzioni di Anatomia e Istologia Patologica, Universita ` di Genova, Genova, Italy Date of submission 13 June 1996 Accepted for publication 11 October 1996 PESCE C., ROSSI R., LENTI E. & TANZI R. (1997) Histopathology 30, 315–318 G-cell density in the antral mucosa: a feasibility study In this work a new method for gastrin-secreting cell (G- cell) density measurement was employed in order to test the hypothesis that G-cell density of the antral mucosa can be estimated with an acceptable degree of error. The zone of antral mucosa where most G-cells are located was demarcated, its area was measured and the G-cells within this area were counted. The variation in the e error of the estimate according to normal distribution theory, and the size of the sampling expected to yield G- cell density values with a given error were assessed. Our data indicate that a very large surface of the G-cell zone should be explored in order to estimate G-cell density with an acceptable degree of error. G-cell density measurement appears not to be feasible on biopsy specimens or, for routine diagnosis, on gastrectomy specimens. Keywords: G-cells, stomach, morphometry Introduction Most gastrin-secreting cells (G-cells) of the stomach 1–2 are found in the distal portion of the antrum, within a zone at the junction between the gastric pits and the pyloric glands that encompasses less than 20% of the distal portion of the antral mucosa. G-cell distribution is more erratic at other sites, such as the proximal portion of the gastric antrum 3 and the duodenum 4 . Over the last 20 years, several quantitative methods have been employed to measure the density of G-cells, which can be revealed with immunofluorescence or immuno- histochemistry techniques by using anti-gastrin anti- bodies. A syndrome of gastrin hypersecretion with clinical features similar to those of Zollinger–Ellison syndrome has been recognized to be due to primary G- cell hyperplasia 5–7 . In cases of this syndrome, G-cells have been reported to show a 20-fold increase in number. G-cell density has also been reported to increase in duodenal ulcer 8 , uraemia 9 , and Helicobacter pylori infection 10 , and to decrease in gastric ulcer 11 . Some of these changes have been challenged in the literature 12 . In this work, a new method for G-cell density measurement was employed in order to test the hypothesis that G-cell density of the antral mucosa can be estimated with an acceptable degree of error. Materials and methods The material examined consisted of formalin-fixed partial gastrectomy specimens from four patients (mean age 70.5 years). The causes for gastric ablation were pancreatectomy for exocrine carcinoma (cases 1 and 3) and duodenal bypass surgery for obesity (cases 2 and 4). The specimens from adjoining areas of the antral mucosa were embedded in Paraplast TM . Sections, 5 mm thick, at least 200 mm apart, were cut from a total of 21 blocks from the four patients (three blocks for cases 1 and 2, seven for case 3, and eight for case 4). One section from each block was stained with haematoxylin- eosin. A total of 48 sections (five for cases 1 and 2, and 19 for cases 3 and 4) were stained with the peroxidase method for human gastrin (Histoscan/Lymphoscan, Biomeda, Italy). G-CELL DENSITY Quantitation was performed with an Optimas TM (Bio- scan, Edmonds, WA, USA) image analysis system. Images were acquired with a Dialux 20EB microscope Histopathology 1997, 30, 315–318  1997 Blackwell Science Limited. Address for correspondence: Dr Carlo Pesce, Cattedra di Istituzioni di Anatomia e Istologia Patologica, Universita ` di Genova, Largo Benzi 10, 16132 Genova, Italy.