The detection of SMARCA4 protein at immunohistochemistry level can be used as a diagnostic criterion, since SMARCA4 protein loss was very rare in other gynecological tumors (absent in HGS-OvCas, present in 4% of clear cell carcinomas, absent in endometrioid cancers and present in 8% of endometrial stromal sarcomas) [173]. This evidence concerns the gene SMARCA4 and endometrioid stromal sarcoma.