While the odds of developing testicular cancer are low (it accounts for only 1% of all cancers), it is the most common kind in men aged 15 to 35. Lance Armstrong—a name synonymous with this type of cancer—was first diagnosed at age 25. Having made a name for himself after beating it, Armstrong's a good example why it's important to stay on the ball. “If you catch it early, the cure rate could be as high as 95 percent,” Dahmer says. Ask your doctor for a screening or practice monthly self exams right after a warm bath or shower, when your skin is relaxed. Using both hands, gently roll each testicle with your thumbs and fingers, feeling for hard lumps, smooth rounded bumps or any changes in size or shape. For more self-exam tips, visit the American Cancer Society.