Differentiation of focal foveolar hyperplasia from hyperplastic polyps in gastric biopsy material.

Our objective was to investigate the question as to whether focal foveolar hyperplasia and hyperplastic polyp can be differentiated in forceps biopsy material from the stomach. Morphometric determination of the height of the epithelium layer in forceps biopsy specimens was obtained from 35 hyperplastic polyps, and forceps biopsy material was obtained from 25 focal foveolar hyperplasias. The diagnosis of hyperplastic polyp was confirmed by subsequent polypectomy. The medians and scatter range of the epithelial layer height were calculated. Using the t-test for independent samples the question was examined as to whether there is any statistically significant difference between hyperplastic polyps and focal foveolar hyperplasia in terms of the parameter "height of the foveolar epithelial layer." The measurements revealed that the average height of foveolar epithelial cells in hyperplastic polyps is 37.70 microns +/- 7.41 microns. In the case of focal foveolar hyperplasia, the corresponding figure was only 24.26 microns +/- 5.11 microns. This difference was statistically highly significant (p < 0.0001). In conclusion, focal foveolar hyperplasia and hyperplastic polyp of the gastric mucosa can readily be differentiated on the basis of architectural and cytological criteria, even in forceps biopsy material. Since the hyperplastic polyp very probably does not evolve from focal foveolar hyperplasia, and the latter is not a pre-neoplastic condition or lesion, it is proposed that focal foveolar hyperplasia should no longer be referred to as "gastric polyp," which would avoid unnecessary follow-up examinations and possibly even surgery.