A condition in which functional endometrial tissue is present outside the UTERUS. It is often confined to the PELVIS involving the OVARY, the ligaments, cul-de-sac, and the uterovesical peritoneum.
An enlarged area of ENDOMETRIOSIS that resembles a tumor. It is usually found in the OVARY. When it is filled with old blood, it is known as a chocolate cyst.