DICER1 and Leydig cell tumor: According to recent studies on the DICER 1 mutation status in ovarian Sertoli–Leydig cell tumors by Kato et al., Karnezis et al., and Yang et al., in a group of patients aged 18 year-old and younger, 94% (17/18) of cases were found to harbor a DICER1 mutation [12,15,23].