KIT and yolk sac tumor: Immunohistochemical examination revealed strong positivity for CD117 and periodic acid-Schiff staining.[8] Primary nonseminoma germ cell tumors of the prostate in KS patients are rare, with only 2 cases reported (a yolk sac tumor and a yolk sac tumor + teratoma).[9,10] To the best of our knowledge, the occurrence of seminoma of the prostate in KS has not been reported.