Please note that the content of this book primarily consists of articles available from Wikipedia or other free sources online. Testicular cancer is cancer that develops in the testicles, a part of the male reproductive system. In the United States, between 7,500 and 8,000 diagnoses of testicular cancer are made each year. Over his lifetime, a man''s risk of testicular cancer is roughly 1 in 250 (0.4%). It is most common among males aged 15 40 years, particularly those in their mid-twenties. Testicular cancer has one of the highest cure rates of all cancers: in excess of 90 percent; essentially 100 percent if it has not metastasized. Even for the relatively few cases in which malignant cancer has spread widely, chemotherapy offers a cure rate of at least 85 percent today. Not all lumps on the testicles are tumors, and not all tumors are malignant; there are many other conditions such as testicular microlithiasis, epididymal cysts, appendix testis (hydatid of Morgagni), and so on which may be painful but are non-cancerous.