Ovarian germ cell cancers are malignancies that arise from germ cells of the embryonic gonad. Although benign germ cell tumors are relatively common, accounting for approximately 20% of all ovarian neoplasms, malignant ovarian germ cell tumors are rare. Weiss et al. (1977) estimated that less than 5% of ovarian cancers are of germ cell origin. [from
OMIM]