Testicular cancer is a malignant growth in a testicle. This is a rather rare form of cancer that affected just under 700,000 men worldwide in 2015. Testicular cancer normally affects younger men, from fifteen to 50. Most lumps in and around the testicles are not dangerous, however you should visit the doctor if you notice a lump on a testicle. A simple ultrasound scan will show if it is cancer or not. Most people who have medical treatment for testicular cancer recover, but it is an advantage if the lump is discovered as soon as possible.