This study tests if adding simvastatin to letrozole helps more than letrozole alone in treating breast cancer that is hormone receptor positive and HER2 negative. Letrozole and simvastatin are drugs that might stop cancer cells from growing. The study will check if the combination reduces a protein called Ki67, which shows how fast cancer cells grow. The study includes two groups: one will take letrozole and simvastatin, and the other will take only letrozole. Both groups will take the medicine for 14 days. After treatment, participants will be monitored for 30 days.

• Study Duration: 14 days with a 30-day follow-up.
• Participants will be checked for increased pain.
• There are no treatment costs; however, participants must meet eligibility criteria.

The study is for postmenopausal women with specific breast cancer characteristics. It's important that participants are not on certain medications and don't have other serious health issues. Participants must be willing to follow the study's schedule and procedures. It's a chance to contribute to research that might improve cancer treatment. Always consult your doctor before joining any study.