RecruitingEarly Phase 1Drug trialLetrozole With and Without Simvastatin for the Treatment of Stage I-III Hormone Receptor Positive, HER2 Negative Breast CancerThis 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 and simvastatin may stop the growth of cancer cells by blocking some of the enzymes needed for cell growth. The addition of simvastatin to letrozole may be more effective at stopping the growth of cancer cells than letrozole alone.