Adenoma (noncystic)

Appendix
Benign tumors
Adenoma (noncystic)

Reviewer: Jaleh Mansouri, M.D. (see Authors page)

Revised: 23 February 2016, last major update August 2012

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PubMed Search: Adenoma appendix

Table of Contents

Definition / general | Microscopic (histologic) description | Microscopic (histologic) images

Cite this page: Adenoma (noncystic). PathologyOutlines.com website. http://www.pathologyoutlines.com/topic/appendixadenoma.html. Accessed May 21st, 2018.

Definition / general

Very rare; by definition, no features of true invasion

Villous adenomas are also called low grade appendiceal mucinous neoplasms

Cystic adenomas are called cystadenomas (see below)

Sporadic, may be associated with colonic adenomas or familial adenomatous polyposis

Microscopic (histologic) description

Resemble colonic tubular, villous or tubulovillous adenomas

Cellular crowding, usually low grade dysplastic changes of nuclear elongation and stratification, pleomorphism and increased mitotic figures

Also mucin depletion

No invasion into appendiceal wall or high grade nuclear atypia

Microscopic (histologic) images

Images hosted on other servers:

Villous type adenoma

Low grade mucinous tumor with villous architecture