What is breast carcinoma?

➢ Breast carcinoma is the most common malignancy of women ➢ Since the mid-1980s the mortality rate has dropped from 30% to less than 20%. ➢ The decrease is attributed to both improved screening, which detects some cancers before they have metastasized, and more effective systemic treatment. ➢ Almost all breast malignancies are adenocarcinomas (>95%). ➢ In the most clinically useful classification system, breast cancers are divided based on the expression of hormone receptors: estrogen and progesterone receptors (ER/PR) and the expression of the human epidermal growth factor receptor 2 (HER2, also known as ERBB2) ➢ They are divided into three major groups: • ER positive (HER2 negative; 50%–65% of cancers) • HER2 positive (ER positive or negative; 10%–20% ofcancers) • Triple negative (ER, PR, and HER2 negative; 10%–20% of cancers)