A drug used with exemestane to treat some postmenopausal women with advanced breast cancer that is hormone receptor positive and HER2 negative. It is also used to treat advanced renal cell carcinoma (a type of kidney cancer) and certain types of pancreatic, lung, and gastrointestinal neuroendocrine tumors. Afinitor is also used to treat renal angiomyolipoma (a type of benign kidney tumor) and subependymal giant cell astrocytoma (a type of benign brain tumor) in patients who have tuberous sclerosis. It blocks a protein involved in cell division, which may help keep abnormal cells, including cancer cells, from growing. It may also prevent the growth of new blood vessels that tumors need to grow. Afinitor contains the active ingredient everolimus. It is a type of kinase inhibitor and a type of angiogenesis inhibitor.