Endometrioid Cancer Transform to Carcinosarcoma after Hormonal Treatment: Epithelial-Mesenchymal Transition during Fertility Preserving Management in Two Women

Endometrial Cancer (EC) is the most common gynecologic malignancy. A significant number of patients are diagnosed during reproductive age in nowadays. The importance of fertility preservation for EC has become more evident than ever before in this patient population. Hormonal therapy for stage IA low-risk endometrial cancer is reported efficient and safe. However, the recurrence rate is high and the pregnancy outcomes are not satisfactory. We report two patients at reproductive age who were diagnosed of endometrioid EC and underwent fertility preservation treatment. Both of them achieved complete remission but later developed carcinosarcoma. This unusual disease progression may imply the underling mechanism of hormonal resistance. The epithelial-mesenchymal transition pathway may be involved in the EC cell evolution.