In the United States, breast cancer is the commonly occurring cancer among women is leading second place related death next to lung cancer. Person having breast cancer also faces health issues like genetic, socio-demographic, and lifestyle features and in addition health challenges of the potential for recurrence or development of a second primary cancer. In treatment of colon cancer, the drug named as Fluoropyrimidines plays a vital role because it provides safe treatment for patients having this disease. In recent days, there is a development in the treatment of breast cancer at the early stages. Fluorouracil, Leucovorin, and Oxaliplatin (FOLFOX) are used for chemotherapy regimens selection by genetic methods. A genetic model is used to evaluate chemotherapy sensitivity by examining gene expression and predictive capacity.