Colon non tumor
Nonneoplastic, noncongenital lesions
Endometriosis

Author: Raul S. Gonzalez, M.D. (see Authors page)

Revised: 10 November 2016, last major update August 2013

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

PubMed search: endometriosis [title] colon

Cite this page: Endometriosis. PathologyOutlines.com website. http://www.pathologyoutlines.com/topic/colonendometriosis.html. Accessed December 5th, 2016.
Definition / General
  • Endometriosis arising within colon
Epidemiology
  • Up to 1 / 3 with endometriosis have involvement of large or small intestine
Sites
  • Usually rectosigmoid or rectovaginal septum (Med Sci Monit 2000;6:787); can involve any portion of colonic wall, from mucosa to serosa
Clinical Features
  • Typically incidental but can cause pain, obstruction, or diarrhea
  • Rarely associated with neoplasms or precancerous changes (Am J Surg Pathol 2000;24:513)
Case Reports
Treatment
Gross Description
  • Serosal and subserosal nodules < 5 cm; smooth muscle hypertrophy may cause obstruction
  • Gray cut surface with minute areas of hemorrhage; can cause adhesions if subserosal
Gross Images
Images hosted on other servers:

Submucosal nodule

Micro Description
  • Endometrial glands and stroma plus hemosiderin in deeper layers of colon; usually surrounded by smooth muscle
  • Epithelium may have inflammation and ulcers, simulating inflammatory bowel disease or solitary rectal ulcer syndrome
  • Often infiltrates along nerves of bowel wall (Hum Reprod 2004;19:996)
  • Mucosa usually normal; bowel wall may be fibrotic; cilia help distinguish endometrial glands from colonic glands
Micro Images
Images hosted on other servers:

Implants within bowel muscle

Within colonic mucosa

Present in wall of colon


Infiltration along nerves

In pericolic lymph nodes (figures 3 / 4)

Positive Stains
Negative Stains
Differential Diagnosis