PTEN and endometrial carcinoma: The remaining 5% have a mesenchymal component such as endometrial stromal sarcoma or are mixed epithelial and stromal tumours such as adenosarcomas and carcinosarcomas.3, 4 Within endometrial carcinoma, the majority of tumours (~80%) are endometrioid adenocarcinomas, which are generally hormone-responsive, are typified by PTEN deletion, and carry a good prognosis.