Risk Factors for Testicular Cancer
The major risk factors for testicular cancer are cryptorchidism (i.e., a condition in which the testes do not descend into the scrotum; also called undescended testicle) and Klinefelter's syndrome (i.e., a congenital disorder caused by an extra X chromosome that results in failure of the testicles and usually is diagnosed after puberty). Other risk factors include a family or personal history of testicular cancer and genetic abnormality of chromosome 12.
Causes of Testicular Cancer
The cause of testicular cancer is unknown. One theory suggests that testicular germ cell tumors form when germ cells develop into sperm cells with 46 chromosomes. Normally, germ cells with 46 chromosomes develop into sperm cells with 23 chromosomes (during a process called meiosis).