Types of Breast Cancer

There are many different types of breast cancer, even if it is often referred to as only one condition. Breast cancer can be classified based on the location of the original tumor, as well as the shape of the cancer cells themselves. For example, the most common type of breast cancer is invasive ductal carcinoma, meaning that it begins in the epithelial cells lining the milk ducts and invades the nearby tissues.

Breast cancers can also be categorized by their hormone status and the type of genes present, which can also indicate which treatments may be effective at treating them. These classifications include:

  • Estrogen-receptor (ER) positive – The cancer is sensitive to estrogen and may therefore respond to hormone therapy.
  • Progesterone receptor (PR) positive – The cancer is sensitive to progesterone, so it may respond to hormone therapy.
  • Hormone receptor (HR) negative – The cancer lacks hormone receptors, so it will probably not respond to treatments that block hormones in the body.
  • HER2 gene positive – The cancer has a specific gene that produces excess amounts of a certain protein that contributes to the growth of the cancer. There are drugs that can shut down that protein, slowing the growth of the cancer.

Once these classifications are made, physicians can organize different types of breast cancer into one of four groups:

  • Luminal A – Tumors test positive for ER and PR, but negative for HER2; they will likely respond well to hormone therapy and perhaps to chemotherapy.
  • Luminal B – Tumors test positive for ER and HER2, but negative for PR; they will probably respond well to chemotherapy and perhaps to hormone therapy and HER2-targeted treatments.
  • HER2 positive – Tumors test positive for HER2, but negative for ER and PR; they will probably respond well to chemotherapy, and perhaps HER2-targeted treatments.
  • Basal-like, also called “triple negative breast cancer” – Tumors that test negative for ER, PR, and HER2; they may respond well to chemotherapy.

Tampa General Hospital treats patients with all types of breast cancer. Our multidisciplinary team of surgeons, radiation oncologists, medical oncologists, and other specialists develop treatment plans specific to each kind of cancer and designed for the individual patient’s needs. Some approaches may include chemotherapy infusions, inpatient or outpatient radiation therapy, and surgical treatment.

If you have been diagnosed with any of the aforementioned types of breast cancer, you can seek treatment at TGH. For a physician referral or to make an appointment, please call (813) 844-2200.