Summary
This early phase I trial tests whether letrozole with simvastatin works better than letrozole alone to stop tumor cell proliferation in patients with stage I-III hormone receptor positive, HER2 negative invasive breast cancer. Letrozole simvastatin may stop the growth of cancer cells by blocking some of the enzymes needed for cell growth. Adding simvastatin to letrozole may be more effective at stopping the growth of cancer cells than letrozole alone.