Risk factors suggesting malignant transformation of gastric adenoma: univariate and multivariate analysis

Since gastric adenomas are precancerous lesions, polypectomy is necessary. However, there have been no reports suggesting factors capable of predicting malignant transformation of gastric adenomas removed by endoscopic snare polypectomy (ESP) or endoscopic mucosal resection (EMR) in Korea, a country in which gastric cancer is a major problem. The aim of this paper was to elucidate the risk factors suggesting malignant transformation of gastric adenomas removed by ESP or EMR at our center. Between November 1994 and June 1999, 118 gastric adenomas diagnosed on the basis of endoscopy and histological examinations of the forceps biopsy specimens obtained were treated by ESP or EMR at our department. Factors capable of predicting malignancy were searched for in the endoscopy reports, still photographs, and histopathological findings. Eight of the 118 adenomas ultimately proved to have malignant foci. In the univariate analysis, four of the variables studied--location, histological type, surface redness, and degree of dysplasia--had a statistically significant relationship with malignant transformation. In the multivariate analysis, only the degree of dysplasia had a statistically significant relationship with malignant transformation. These results suggest that a diagnosis of high-grade dysplasia in forceps biopsy material should be considered an absolute indication for ESP or EMR.