What is testicular cancer?

The body is made up of many types of cells. Normally, cells grow, divide and then die. Sometimes, cells mutate (change) and begin to grow and divide more quickly than normal cells. Rather than dying, these abnormal cells clump together to form tumors. If these tumors are cancerous (also called malignant tumors), they can invade and kill your body's healthy tissues. From these tumors, cancer cells can metastasize (spread) and form new tumors in other parts of the body. By contrast, noncancerous tumors (also called benign tumors) do not spread to other parts of the body.Testicular cancer begins in one or both of the testicles. The testicles are located in the scrotum, the skin “sack” that hangs beneath the penis. They manufacture male hormones and produce sperm. A normal adult testicle is about the size of a golf ball and is round, smooth and firm.