All breast cancer needs to be treated. Some types of breast cancer are more serious than others. DCIS is the least serious type of breast cancer and i. Sep 11, - Being a woman and getting older are the main risk factors for breast cancer. Studies have shown that your risk for breast cancer is due to a combination of factors. The main factors that influence your risk include being a woman and getting older. Most breast cancers are found in women who are 50 years old or older.