A malignant tumor predominantly affecting young men and often associated with cryptorchidism. Seminoma is the most frequently seen malignant testicular germ cell tumor, followed by embryonal carcinoma and yolk sac tumor. The disease is MONDO_0003510 (malignant testicular germ cell tumor). Also known as: malignant germ cell neoplasm of testis, malignant germ cell neoplasm of the testis, malignant germ cell tumor of testis, malignant germ cell tumor of the testis, malignant germ cell tumour of testis, malignant germ cell tumour of the testis, malignant testicular germ cell neoplasm, testicular ca. (no germ/tropho.).