Men between the ages of 20 and 40 are susceptible to tumors, with germ cell tumors being the most common, and testicular cancer is one of them. Testicular cancer is a common cancer in men between the ages of 20 and 34. Caucasian men are more likely to develop testicular cancer than yellow men. So how is testicular cancer caused? There are several main causes: 1. Cryptorchidism Normally, the testicles will descend to the scrotum. If the testicle does not descend to the scrotum but stays in the abdominal cavity or groin, the chances of testicular cancer are greatly increased. Even if the testicles are surgically moved to the scrotum, it will not help. 2.Klinefelters syndrome Klinefelters syndrome is a kind of sex chromosome abnormality disease, the symptoms of which are low testosterone level, sterility, full breasts and small testes. 3.Genetic factors The occurrence of testicular cancer is related to genetic factors. If a person’s father or brother has testicular cancer, his chance of getting this disease is higher than others. How testicular cancer is caused 4.Abnormal testicular development Men with abnormal testicular development are prone to testicular cancer. 5.History of testicular cancer Men who have a history of testicular cancer are also prone to testicular cancer in the other testicle.