Final answer:
A change in size or a lump in the testicle is a sign of testicular cancer. Diagnosis involves a physical exam and diagnostic tests, and treatment typically includes surgery, possibly along with radiation or chemotherapy.
Step-by-step explanation:
One sign of testicular cancer is a change in size or the presence of a lump in the testicle. Other symptoms may include swelling, pain, a feeling of heaviness in the scrotum, and fluid in the scrotum. Testicular cancer is particularly common in young males and is more prevalent in those of European ancestry. The most reliable way of diagnosing this cancer is through a physical examination, detecting a lump, followed by diagnostic tests such as an ultrasound and blood tests for tumor markers. Treatment generally involves surgery to remove the affected testis, and may be accompanied by radiation therapy or chemotherapy. Testicular cancer has one of the highest cure rates among cancers when detected early.