Definition

Endometriosis is the ectopic location of endometrial tissue. This includes both stromal and glandular tissue. Endometriosis is known to occur at many varied sites.

Epidemiology

• Endometriosis occurs in 7-12% of women.
• Endometriosis occurs in up to 50% of premenopausal women.
• Endometriosis occurs particularly in infertile women (~40%) and those with chronic pelvic pain (>70%).
• Note that there has been no ethnic linking to endometriosis.

Etiology, Pathophysiology, and Risk Factors

The pathophysiology of endometriosis is not well understood. However, several theories exist:

• Retrograde menstruation (NOTE: most endometriosis occurs in local pelvic sites accessible to retrograde menstruation)
• Immunodeficiency (limiting the clearance of transplanted tissue)
• Coelomic metaplasia (some factor induces the change of undifferentiated peritoneal cells into endometrial cells)
• Lymphatic flow from uterus to ovaries
• Hematogeneous spread to distant sites

Risk factors for endometriosis

• Family history of endometriosis
• Obesity (potential estrogen link)
• Chronic pelvic pain
• Infertility

Clinical Presentation and Diagnostic Approach

• Many women with endometriosis are asymptomatic
• The classical triad of symptoms, however, are
  • Dysmenorrhea (may be exaggerated or occurring before menses)
  • Dyspareunia
  • Infertility
• The endometriosis patient will likely have suffered from chronic pelvic pain
• Pain correlates well with the severity of lesions: this pain may extend well beyond the lesion sites
• Systemic involvement: for example, cyclic diarrhea with menses.
• Adenexal mass
• Low-level echoes on ultrasound
  • Imaging should only be performed on the presence of an adenexal mass

The diagnosis of endometriosis is made via

• Laparoscopy with biopsy and histology
  • Both glandular and stromal tissue must be found for diagnosis to be made

Management

Can be divided into Medical or Surgical management

Medical management of endometriosis

Non-Hormonal

• NSAIDs

Hormonal

• BCP/MPA
• DMPA
• Danazol
• GnRH analogues

Surgical management of endometriosis

• Conservative: laparoscopic excision of lesions with restoration of normal anatomy, such as adhesiolysis, ablation of endometrial spot
• Radical: hysterectomy with bilateral salpingo-oophorectomy, if Hormonal replacement therapy is required, progesterone should be given otherwise the estrogen dependent endometrioma may grow on pelvic tissue.