Dear Brenda9020: Whether or not to do chemotherapy depends on many factors including the size of the tumor, the histology (the way it looks under the microscope), estrogen and progesterone status, her2 neu status, etc. Basically, the purpose of chemotherapy is to reduce the risk of recurrence and/or metastasis. Often oncologists will estimate the risk of recurrence as well as the estimated benefit of chemotherapy and base recommendations on this. When the tumor is hormone receptor positive (positive for estrogen and/or progesterone receptors), there is generally felt to be a benefit to endocrine therapy. Some patients will also have an additional benefit to chemotherapy. One test that has been used to try to better estimate outcome with endocrine treatment alone versus endocrine treatment plus chemotherapy is the Oncotype DX assay which is a test done on the cancerous tumor itself and looks at some of the genes expressed by the cancer. Certain profiles have been associated with more or less benefit to chemotherapy. You may want to discuss this further with your oncologist. Your oncologist would be the most appropriate person who can discuss the risks/benefits of various options with you so that you can make an informed decision. Radiation is generally used to reduce the risk of local recurrence and is generally given after breast conserving surgery or following mastectomy for those individuals at particularly high risk for local recurrence (such as those with large tumors or significant lymph node involvement). Radiation is not used to address prevention of recurrence anywhere else in the body as it is a local treatment only.
Gwen