Genomic alterations in the PI3K pathway were weakly associated with longer overall survival for patients with ovarian endometrioid carcinomas (Χ12 = 2.7, P = 0.101, Supplementary Fig. S11A), whereas no differences in overall survival were observed in patients with ovarian mucinous carcinomas (Χ12 = 2.5, P = 0.114, Supplementary Fig. S11B). Here, PIK3CA is linked to ovarian endometrioid carcinoma.