Ovarian Borderline Epithelial Tumors

ABSTRACT

Ovarian borderline epithelial tumors are abnormal proliferative epithelial lesions without obvious invasion of the stroma of the ovary, a finding distinguishing between borderline tumors and carcinoma. There have been controversies regarding the terminology and diagnostic feature of the tumors, even though these tumors have been accepted as a distinct entity in WHO classification of ovarian epithelial tumors. This review is limited to serous and mucinous borderline tumors which are the most common and about which many clinicopathological studies have been undertaken. It has been agreed that "micropapillary carcinoma" espoused by a group of pathologists is a micropapillary variant of serous borderline tumor in the borderline ovarian tumor workshop. Diagnostic criteria of invasive implants needs further study but invasion of underlying normal tissue was reported to be correlated well with prognosis. Other issues such as diagnostic criteria of microinvasion and multiplicity of serous borderline tumors have been presented. The sole diagnostic criteria agreed upon for the diagnosis of intraepithelial carcinoma in the mucinous borderline tumor was the presence of severe cytological atypia. It was also agreed that the ovarian tumors associated with pseudomyxoma peritonei are almost invariably from gastrointestinal tract, usually appendix. Stratification and complex intracystic growth without severe cytological atypia are considered to be characteristics of mucinous borderline tumors. Diagnostic criteria of microinvasion and two types of invasion, expansile and infiltrative invasion, have also been discussed.