pathology

Last reviewed 12/2022

• most commonly - endometriotric deposits are multiple small (<1cm) raised blue-black nodules - they appear as if ink has been injected under the peritoneum. If the condition is severe then the nodules may be larger and surrounded by variable amounts of fibrosis
  
  
• other 'atypical/subtle' lesions commonly seen include red implants (petechial, vesicular, polypoid, haemorrhagic, red flame-like) and serous or clear vesicles (1)
  
  
• involvement of the ovary may lead to the formation of an endometrioma (chocolate cyst)
  
  
• deep infiltrating nodules extend more than 5mm below the peritoneal surface and may penetrate or adhere to other structures (eg. bowel, bladder, ureters, vagina) (1)
  
  
• extensive pelvic damage due to fibrosis and adhesions may occur in chronic disease
  
  
• microscopically endometriotic deposits contain glands and stroma. There is also a variable amount of fibrosis and bleeding. The endometriotic deposits may be out of phase with the woman's menstrual cycle. However, like normal endometrial tissue, the deposits decidualize during pregnancy

Reference:

• (1) RCOG (2006) The investigation and management of endometriosis. Royal College of Obstetricians and Gynaecologists.