What are germ cell tumors?
Germ cells tumors are malignant (cancerous) or non-malignant (benign, non-cancerous) tumors that are comprised mostly of germ cells. Germ cells are the cells that develop in the embryo (fetus, or unborn baby) and become the cells that make up the reproductive system in males and females. These germ cells follow a midline path through the body after development and descend into the pelvis as ovarian cells or into the scrotal sac as testicular cells. Most ovarian tumors and testicular tumors are of germ cell origin. The ovaries and testes are called gonads. Tumor sites outside the gonad are called extragonadal sites. The tumors also occur along the midline path and can be found in the head, chest, abdomen, pelvis, and sacrococcygeal (lower back) area. Germ cell tumors are diagnosed in about 900 children each year. Germ cell tumors account for 16 percent of all cancers diagnosed in adolescents between the ages of 15 and 19 years old, and nearly 4 percent of cancers diagnosed in children y
