Possible neoplastic transformation within gastric hyperplastic polyp. Application of endoscopic polypectomy.

A total of 263 gastric hyperplastic polyps, which had been removed endoscopically from 202 patients, were clinicopathologically analyzed. Among these polyps, there were nine polyps with neoplastic components (3.4%), corresponding to adenoma in five lesions and mucosal adenocarcinoma in four lesions. Comparing the neoplastic transformed polyps with the pure hyperplastic polyps, there was no significant difference according to age, gender, location, gross appearance, or size. However, the transformed polyps which were located in the lower third of the stomach were larger in size (mean, 20.8 mm) and were more likely to be found among older patients (mean, 75.8 years) than were the pure hyperplastic polyps (mean size and age: 14.5 mm and 61.8 years). These results may indicate the possibility of a different carcinogenesis belonging to gastric hyperplastic polyps by location, and this finding seems to be significant in the application of endoscopic polypectomy.