Rare lesions are seen as far afield as small bowel, kidneys, lungs and brain. Suggests that occurrence of endometriosis may be due to hematogenous or lymphatic spread from the endometrium. It is proposed that endometriosis arises from celomic metaplasia of the peritoneum. The clinical presentation depends on the site of endometriosis. Dysmenorrhea, cyclic abdominal pain and dyspareunia are common symptoms.
Infertility occurs in about a third of affected women.
Dense fibrous adhesions may surround the foci. Histology Microscopic diagnosis of endometriosis is made by the presence of ectopic endometrial glands and stroma. In others, the endometrial tissue is inactive and no evidence of past bleeding is seen. When endometriosis develops in a muscular viscus, the smooth muscle around it is often hyperplastic. Clinical behavior Benign with no malignant potential.