Definition of Germ Cell Tumor

Germ cell tumor is a tumor that arises from a germ cell. A germ cell tumor may arise within the gonads (in the ovary or testis). Most testicular tumors, in fact, are germ cell tumors. Germ cell tumors also may arise in extragonadal sites, reflecting the fact that germ cells travel to diverse areas of the body, such as the chest, abdomen, and brain. Germ cell tumor is also referred to as germ cell cancer.