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

Revised: 26 January 2016, last major update August 2012

Copyright: (c) 2003-2016,, Inc.

PubMed Search: Endometriosis appendix
Cite this page: Endometriosis. website. Accessed June 17th, 2018.
Definition / general
  • Women of reproductive age or post-menopausal women with hormone replacement therapy
  • Appendix is common site of intestinal involvement
  • Associated with endometrial hyperplasia, MMMT, endometrial carcinoma
Case reports
Gross description
  • Serosal nodule or blood-filled ("chocolate") cyst
  • Rarely causes appendiceal rupture
Microscopic (histologic) description
  • Endometrial glands, endometrial stroma, hemosiderin
  • May have muscular hypertrophy, overlying mucosa may be ulcerated
  • No dysplasia
Microscopic (histologic) images

Images hosted on other servers:

Endometriosis of appendix

Positive stains
  • CD10 (stroma)
Differential diagnosis
  • Invasive well differentiated adenocarcinoma