Source:http://linkedlifedata.com/resource/umls/id/C1332596
NCI: A low grade ovarian epithelial tumor composed of an admixture of two or more of the five major cell types: serous, mucinous, endometrioid, clear cell, and Brenner/transitional. The second or second and third cell types must comprise alone or together at least 10% of the tumor epithelium. The majority of patients present with stage I tumor and a minority present with bilateral disease. Morphologically, it shows papillae with detached cell clusters. Microinvasion may be seen rarely. (WHO 2003)