What is the rate of incidence for extragonadal germ cell tumors?

For men 15 to 35 years old, malignant (cancerous) germ cell tumors are the most common type of cancer. The majority (75-95 percent), however, of germ cell tumors for this age group are located in the gonads, or reproductive organs, not outside the reproductive organs. Even given the relatively small number of cases, extragonadal germ cell tumors tend to be deadly; about 80 percent of people with these tumors have a poor prognosis (chance of recovery).