text: Testicular cancer is a rare disease in men caused by abnormal growth of cells of the testicle. The testicles (or testes) are located inside the scrotum, the loose bag of skin that hangs below the penis. Each testicle (or testis) produces sperm.\n\n\nThe male pelvis\n\nCancer\nThe building blocks of the body are tiny cells, which normally repair and reproduce in a controlled process. With cancer, this process goes wrong and cells can divide and grow in an uncontrolled way, causing a lump on or within the part of the body affected. If this tumour contains cells that are able to invade neighbouring tissues or organs, it is known as malignant. If the tumour does not do this, it is termed benign.