Categories of Breast Cancer
Noninvasive (in situ) cancer. This occurs only in the ducts or lobules and doesn’t spread to nearby areas. If not treated, it can later grow into a more serious, invasive type of cancer. If you are diagnosed with noninvasive carcinoma, your chances of surviving are very high if you don’t wait to treat it. If you do wait, you’re at risk of the cancer becoming invasive. Invasive cancer is harder to treat.
Types of Noninvasive Cancer
- Ductal Carcinoma in situ (DCIS). Cancer starts inside the milk ducts.
- Lobular Carcinoma in situ (LCIS). A marker for the risk of breast cancer.
Invasive (infiltrating) cancer. This kind of cancer has started to spread to nearby areas. This type is much more serious than noninvasive cancer. It often invades nearby lymph nodes first. It can then spread to other parts of your body through your bloodstream and lymphatic system. Treatment for invasive cancer is usually a more difficult, long-term process.
Subtypes of Invasive Breast Cancer
- Invasive Ductal Carcinoma. Cancer has spread to surrounding breast tissues. Most common form of invasive breast cancer.
- Tubular Carcinoma of the Breast
- Medullary Carcinoma of the Breast
- Mucinous Carcinoma of the Breast
- Papillary Carcinoma of the Breast
- Cribriform Carcinoma of the Breast
- Inflammatory Breast Cancer. A rare and aggressive form of breast cancer that usually starts with the reddening and swelling of the breast instead of a distinct lump.
- Invasive Lobular Carcinoma. Cancer that beings in the milk-carrying ducts and spreads beyond it.
Additional Types of Cancer
- Male Breast Cancer. The lifetime risk of a male being diagnosed with breast cancer is about 1 in 1,000. Usually invasive at the time of diagnosis.
- Paget’s Disease of the Nipple. Cancer cells collect in or around the nipple. May be associated with in situ or invasive cancer.
- Phyllodes Tumors of the Breast. Tumor cells grow in a leaf-like pattern. Although most phyllodes tumors are benign (noncancerous), some are malignant (cancerous) and some are borderline (in between noncancerous and cancerous).
- Metastatic Breast Cancer. Breast cancer that has spread to other parts of the body such as the bones, liver, lungs, or brain.
Breast Cancer Molecular Subtypes:
(Breast cancers can be described by subtypes)
- Her2-Positive. Breast cancer that test positive for the protein human growth factor receptor 2 (HER2), which promotes the growth of cancer cells.
- Luminal A. A high expression of hormone receptors (estrogen receptor) and progesterone receptor, and low expression of the cell-growth marker KI67 and the HER2.
- Luminal B. Estrogen receptor positive and is defined by the increased proliferation, relative resistance to chemotherapy compared with other highly proliferative breast cancers.
- Triple negative breast cancer. This cancer does not express the genes for estrogen receptor, progesterone receptor, or HER2.
How Breast Cancer Spreads
Breast cancer can spread by growing into nearby tissues in the breast or when the cancer cells get into and travel through the blood or lymph systems. When this happens, cancer cells may be found in the lymph nodes in the armpit. These lymph nodes are called axillary lymph nodes. They are often checked for cancer as part of the diagnosis process. If the cancer reaches these nodes, it may have spread to other parts of the body.
Breast cancer that has spread to other organs of the body is called metastatic breast cancer. When breast cancer spreads to other parts of the body, it most often goes to the brain, bones, liver, or lungs.