Table of Contents
Definition / general | Diagrams / tables | Treatment | Gross description | Gross images | Microscopic (histologic) description | Microscopic (histologic) images | Cytology images | Positive stains | Differential diagnosis | Additional referencesCite this page: Endometriosis. PathologyOutlines.com website. http://www.pathologyoutlines.com/topic/uterusendometriosis.html. Accessed April 26th, 2018.
Definition / general
- Endometrial tissue outside the uterus; closely related to adenomyosis
- Women 20 - 30 years old, up to 10% of all women affected
- Consists of functional layers of endometrium that go through menstrual changes, although is more proliferative than normal endometrium
- Causes pain, infertility (1/3 of women are infertile)
- Causes: regurgitation (retrograde menstruation), metaplasia and angiolymphatic dissemination (to lungs, nodes); metaplastic change of secondary mullerian system represented by pelvic mesothelium
- Sites: ovaries > uterine ligaments > rectovaginal septum > pelvic peritoneum > scar
- Rarely in lymph nodes, usually with cuboidal epithelium, no stroma, limited to capsule and resembles tubal epithelium; call endosalpingiosis
- Rarely has extensive intestinal tract involvement, resembling other intestinal diseases (Am J Surg Pathol 2001;25:445)
- May undergo malignant transformation (Hum Pathol 2000;31:456)
- Malignant tumors: endometrioid > clear cell, endometrial stromal sarcoma and MMMT
- Organizing hemorrhage may cause adhesions, ovarian chocolate cysts
Treatment
- Hormones, surgery (including robotic assisted laparascopy, JSLS 2011;15:387)
Gross description
- Blue cystic nodules surrounded by fibrosis
- Rarely, polypoid masses simulating a neoplasm (Am J Surg Pathol 2004;28:285)
Microscopic (histologic) description
- Contains at least two of three features - endometrial glands, endometrial stroma and hemorrhage
- May be a dense fibrous mass
- May undergo mucinous metaplasia (also called endocervicosis or myxoid change)
- Associated with perineurial invasion
- May be associated with skeletal muscle regeneration (Am J Surg Pathol 2010;34:10)
Microscopic (histologic) images
Cytology images
Images hosted on PathOut server:
Contributed by Dr. Carmen Luz:
Positive stains
- CD10 (endometrial stromal cells, Arch Pathol Lab Med 2003;127:1003), p63 (nuclear staining in glandular component, Arch Pathol Lab Med 2007;131:1099)
- Also CK7, ER, PR, usually CA125 (Hum Pathol 2008;39:954)
Differential diagnosis
- Well differentiated adenocarcinoma if endocervicosis present
- Pseudomyxoma peritonei if myxoid change (may also be caused by endometriosis, Am J Clin Pathol 2000;113:860)