Testicular cancer always occurs in both teste either at the same time or successively and about 2-3 percent one testis?

This statement is not entirely accurate. While testicular cancer can occur in both testes, it does not always do so. In fact, the majority of testicular cancers are unilateral, meaning they occur in only one testis. Only a small percentage, approximately 2-3%, of testicular cancers are bilateral, meaning they occur in both testes. Additionally, testicular cancers do not necessarily occur at the same time in both testes. They can occur successively, with one testis being affected first and the other developing cancer later on.