HI, My mother has been diagnosed with PT4bN0M) breast cancer. Surgery was successful. Lymph nodes are free of tumor. No metastasis . Her pathology report says 3) Estrogen Receptor (ER) - Poitive (Allred Score 3+3 =6) 4) Progestrone Receptor (PgR) - Positive (Allred score 3+3 = 6) 5) Her-2/neu - Negative Her medical oncologist said 4 cycles chemotherapy is required. and also 5 years hormone therapy . Completed 1st cycle on 22nd Aug, 2012 with endoxan, adrim(remember only those 2) When there is no metastasis and -ve lymp nodes, why chemotherapy is required?