ESR1 and endometrial stromal tumor: In most adenosarcomas with a low-grade stromal component, the stromal element expresses estrogen receptor, progesterone receptor, CD10, WT1, smooth muscle actin, low MIB1 proliferation index and is negative for P53.6, 9 The CD10 is diagnostically a useful marker for endometrial stromal tumors and can also be used in establishing the diagnosis of uterine adenosarcomas.6 Alterations in the PIK3CA/AKT/PTEN pathway were also found.9 Immunohistochemistry of our patient presented high level of estrogen/progesterone receptors, smooth muscle actin positivity and low MIB 1 proliferation index.