Breast cancer treatment options depend on the stage of the cancer. Most women with breast cancer in stages I, II, or III are treated with surgery, often followed by radiation therapy. Many women also get some kind of systemic drug therapy (medicine that travels to almost all areas of the body) . According to the search results, a mastectomy may be required for the following stages of breast cancer:

• Stage I: Surgery is the main treatment for stage I breast cancer. These cancers can be treated with either breast-conserving surgery (BCS; sometimes called lumpectomy or partial mastectomy) or mastectomy. The nearby lymph nodes will also need to be checked, either with a sentinel lymph node biopsy (SLNB) or an axillary lymph node dissection (ALND) .

• Stage II: Stage II cancers are treated with either breast-conserving surgery (BCS; sometimes called lumpectomy or partial mastectomy) or mastectomy. The nearby lymph nodes will also be checked, either with a sentinel lymph node biopsy (SLNB) or an axillary lymph node dissection (ALND). If cancer is found in the lymph nodes during mastectomy, radiation therapy might be recommended.

• Stage III: In stage III breast cancer, the cancer has spread further into the breast or the tumor is a larger size than earlier stages. A mastectomy may be a treatment option for stage III breast cancer after chemotherapy or radiation therapy.

It is important to note that the choice between having a mastectomy and a lumpectomy is a highly personal one, and both procedures are equally effective in preventing a recurrence of breast cancer. The decision should be made based on the patients personal preferences and other information about their breast cancer.