Breast Cancer Awareness In recent years, researchers have become aware that breast cancer is not a single disease but a variety of cancers affecting the breasts. One of the most aggressive types of breast cancer called "triple negative" seems to target poor black and Hispanic women under the age of 40, according to an article published this year in CANCER, a journal of the American Cancer Society. The study also found that women with triple-negative breast cancer have a lower survival rate than women with other breast cancers. Triple-negative breast cancer lacks three important tumor markers: estrogen receptor (ER), progesterone receptor (PR), and HER2. This makes it resistant to hormone adjuvant therapy.