PTEN and endometrial endometrioid carcinoma: In the endometrioid SEO subgroup, we found PTEN mutations in 72% (ovarian counterpart)–75% (endometrial counterpart), which was similar to the mutation rate found in endometrioid endometrial carcinomas by McConechy et al. (67%).24 In contrast, they showed that PTEN mutations are less common in endometrioid ovarian carcinomas, found in only 17%.