Endometrioid tumors account for approximately 20% of all ovarian cancers and are mostly malignant (endometroid carcinomas). They are made of tubular glands bearing a close resemblance to benign or malignant endometrium. 15-30% of endometrioid carcinomas occur in individuals with carcinoma of the endometrium, and these patients have a better prognosis. They appear similar to other surface epithelial-stromal tumors, with solid and cystic areas. 40% of these tumors are bilateral, when bilateral, metastases is often present