Ovarian germ cell neoplasms are derived from primordial germ cells of the ovary (figure 1). They may be benign or malignant. These neoplasms comprise approximately 20 to 25 percent of ovarian neoplasms overall, but account for only about 5 percent of all malignant ovarian neoplasms [1-3]. Ovarian germ cell neoplasms arise primarily in young women between 10 and 30 years of age and represent 70 percent of ovarian neoplasms in this age group .
The pathology, clinical manifestations, and diagnosis of ovarian germ cell neoplasms are reviewed here. Treatment of malignant germ cell neoplasms of the ovary as well epithelial ovarian carcinoma is discussed separately. (See "Treatment of malignant germ cell tumors of the ovary" and "Epithelial carcinoma of the ovary, fallopian tube, and peritoneum: Clinical features and diagnosis".)
OVERVIEW OF OVARIAN GERM CELL TUMORS
Histopathology overview — The histological types of ovarian germ cell neoplasms (OGCNs) that arise from the ovary are similar to those developing in the testes of men (table 1) [2,5]. (See "Anatomy and pathology of testicular tumors".)
Ovarian germ cell neoplasms can be broadly divided into those that differentiate towards embryo-like neoplasms (teratomas and their subtypes and dysgerminomas) and those that differentiate primarily toward extraembryonic fetal-derived (placenta-like) cell populations or a mixture of both. Categories include: