Below is an instruction from Human. Write a response.
    ### Instruction:
    What is (are) Endometrial Cancer ?
    ### Response:
    Key Points
                    - Endometrial cancer is a disease in which malignant (cancer) cells form in the tissues of the endometrium.     - Obesity and having metabolic syndrome may increase the risk of endometrial cancer.    - Taking tamoxifen for breast cancer or taking estrogen alone (without progesterone) can increase the risk of endometrial cancer.
    