Ovary, endometrioid carcinoma

Endometrioid carcinoma is the second most common ovarian epithelial malignancy. It is characterized by epithelium resembling uterine endometrium. Association with endometriosis is common, and risk factors are thought to be shared with endometrial endometrioid carcinoma including unopposed estrogens and Lynch syndrome. In this case, the diagnostic features are confluent glandular proliferation with cribriform and villoglandular growth along with stromal invasion. The epithelial cells show columnar and polarized morphology. Focal mucinous or squamous differentiation does not alter the classification.