[A case of testicular tumor in a patient with Down's syndrome: a case report]

A 20-year-old man with Down's syndrome was admitted to our hospital because of a painless, swollen mass in the left scrotum. High inguinal orchiectomy was performed under the diagnosis of testicular tumor, and pathological findings revealed mixed germ cell tumor. Seventeen cases including our case, reported as testicular tumor with Down's syndrome, are herein reviewed.