Spontaneous sertoli cell tumor with cryptorchism in a beagle dog.

A male one year-old beagle dog with unilateral cryptorchism was presented for investigation of reduced appetite. Abdominal sonography and radiography demonstrated abnormal enlargement of the left testicle in the abdominal cavity. Both the retroperitoneal cryptorchid testicle and the other contralateral testicle were removed surgically. The retroperitoneal cryptorchid testicle was an enlarged, firm and bulging sphere mass. The cut surface revealed a homogeneous white color. The contralateral testicle in the scrotum showed an almost normal appearance. Histopathologically, the retroperitoneal cryptorchid testicle was diagnosed as a Sertoli cell tumor. This report describes a case of Sertoli cell tumor with cryptorchism in a beagle dog.