A Case of Pseudoinvasion in Peutz-Jeghers Polyposis

Kim, Sang Pyo; Lee, Sang Sook; Chang, Eun Sook

Abstract

Peutz-Jeghers polyp with pseudoinvasion is characterized by the presence of mucosal islands within muscle layer often associated with mucinous cysts. It occurs when mucosal components completely penetrate the muscularis propria, and shows no cytologic signs of malignancy. In most instances, the lesion may be the result of forces exerted during intussusception in the involved small intestine. We describe a case of Peutz-Jeghers polyposis with pseudoinvasion in a 24-year-old female patient. This patient presented with intussusception and a segmental resection of the ileum was performed. Microscopically, it disclosed a hamartomatous polyp with pseudoinvasion. There were glandular islands and mucinous cysts embedded within the bundle of muscle, layer, extending, to the subserosa. There was o evidence of cellular dysplasia or desmoplasia.