Disclosed herein are methods of treating one or more tumors by administering to the subject a therapeutically effective amount of a combination of RAD1901 or solvates (e.g., hydrate) or salts thereof and one or more second therapeutic agent(s) (e.g., everolimus). The cancer is an estrogen-dependent cancer, such as breast cancer, ovarian cancer, colon cancer, endometrial cancer, or prostate cancer.
