PTEN and serous adenocarcinoma: Inactivation of PTEN occurred only by copy number loss in high-grade serous carcinomas and by mutations in endometrioid carcinomas, while PTEN was not altered in clear cell carcinomas, and the differential distribution between histological subtypes was statistically significant (P = 0.033 for the detection of any PTEN alteration and P < 0.001 for different alteration types, Fig. 1d and Additional file 7).