Breast cancer

Breast cancer is the most common malignant tumor in women (1). 99% of breast cancers concern women and almost 1 in 8 women develops breast cancer during her lifetime (1).

Even though breast cancer is the deadliest cancer (2), detected early, breast cancer heals in 9 out of 10 cases (1).

  • The most frequent breast cancers are adenocarcinomas (in 95% of cases) (1).
  • In 2018, in France, it is estimated that (1):
    • nearly 59,000 new breast cancers have been detected,
    • more than 12,100 deaths have been attributed to this cancer,
  • Thus, breast cancer is the primary cause of death in women (14% of female deaths from cancer in 2018) (2).
  • However, over the past 30 years, even though the annual number of new cases of breast cancer in women has increased (+ 1.1% per year on average), the mortality rate has decreased year after year (2).
  • The management of breast cancer calls for a multidisciplinary team: surgeon, radiotherapist, oncologist, treating physician, who in consultation determine the treatment best suited to each woman (1).
  • The choice of treatment depends on (1):
    • the type of breast cancer and its characteristics defined by its anatomopathological analysis;
    • whether or not there are hormone receptors for estrogen and  progesterone at the level of cancer cells (hormone-dependent / hormone receptor-positive breast cancer);
    • the presence of HER2 (human epidermal growth factor receptor 2) found on the surface of mammary cells (tumor HER 2 positive);
    • the location of the tumor in the breast;
    • its size, whether or not there is damage to the lymph nodes or metastases;
    • the patient’s state of health.
  • The treatment of breast cancer is mainly based on surgery, supplemented, depending on the case, by other therapeutic methods (radiotherapy, chemotherapy, hormone therapy) (1).