In what cells do testicular cancer arise?

Testicular cancer primarily arises from germ cells, which are the cells responsible for producing sperm. The two main types of testicular germ cell tumors are seminomas and non-seminomas. Additionally, testicular cancer can also originate from other cell types, such as Leydig cells and Sertoli cells, but these are less common. Overall, germ cell tumors account for the majority of testicular cancer cases.