Page 599 - Textbook of Pathology, 6th Edition

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Figure 20.41 Hamartomatous polyps: Peutz-Jeghers polyp.

Inflammatory Polyps (Pseudopolyps) Lymphoid Polyps
Inflammatory polyps or pseudopolyps appear due to re- Reactive hyperplasia of lymphoid tissue that is normally also
epithelialisation of the undermined ulcers and overhanging more prominent in the rectum and terminal ileum, gives rise
margins in inflammatory bowel disease, most frequently in to localised or diffuse lymphoid polyps, also called rectal
ulcerative colitis (colitis polyposa) and sometimes in Crohn’s tonsils. Localised form occurs more often in the rectum in
disease. elderly, while diffuse form is seen at younger age and in CHAPTER 20
children.
Grossly, they are usually multiple, cylindrical to rounded
overgrowths of mucosa and may vary from minute Grossly, they are solitary or multiple, tiny elevated lesions.
nodules to several centimeters in size. Microscopically, they are composed of prominent
Microscopically, the centre of inflammatory polyp lymphoid follicles with germinal centres located in the
consists of connective tissue core that shows some submucosa and mucosa, and are covered by epithelium
inflammatory cell infiltrate and is covered superficially that may be inflamed.
by regenerating epithelial cells and some cystically-dilated They are benign lesions and have to be distinguished from
glands. malignant lymphoma.

These lesions have no malignant potential; carcinomas B. NEOPLASTIC POLYPS (ADENOMAS) The Gastrointestinal Tract
seen in long-standing cases of ulcerative colitis arise in the
region of epithelial dysplasia and not from the polyps. Neoplastic polyps are colorectal adenomas which have
potential for malignant change while polypoid carcinoma is

Figure 20.42 Juvenile polyp.