Definition of breast cancer
Definition of breast cancer
Breast cancer is a type of cancer that begins in the breast. Cancer begins when cells begin to grow uncontrollably. (For more information about how cancer begins and spreads, see What is 10 cancer symptoms that you are likely to ignore?)
Breast cancer cells usually form a tumor that can often be seen on an X-ray or felt like a lump. Breast cancer occurs almost entirely in women, but men can also develop Breast cancer.
It is important to understand that most Breast lumps are benign, not cancer (malignant).
Non-cancerous breast tumors are abnormal growth, but they do not spread outside the breast. It is not life threatening, but some types of benign breast lumps can increase a woman’s risk of developing Breast cancer. Any lumps or changes in the breast should be examined by a healthcare professional to determine whether they are benign or malignant (cancer) and whether they can affect the risk of cancer in the future.
Definition of Breast cancer and Where breast cancer begins
Breast cancers can begain from different parts of the breast.
- Most breast cancers begin in tubes that carry milk to the nipple (ductal cancer)
- Some begin in the glands that make breast milk (lobular cancer)
- There are also other less common types of breast cancer such as phyllos tumors and angiosarcoma.
- A small number of cancers begin in other breast tissue. These cancers are called sarcomas and lymphomas and breast cancers are not really considered.
Although many types of breast cancer can cause a breast tumor (lump), not all do this.
Types of breast cancer
There are many different types of breast cancer, the most common of which are on-site canal cancer (DCIS) and invasive cancer. Others, such as phyllodes tumors and angiosarcoma are less common.
Once the biopsy is performed, the breast cancer cells are analyzed for proteins called estrogen receptors, progesterone receptors and HER2 receptors. Cancer cells are also examined closely in the laboratory to determine their degree. Existing specific proteins and tumor degrees can help determine treatment options.
How does breast cancer spread
Breast cancer can spread when cancer cells enter the blood or lymphatic system and are transported to other parts of the body.
The lymphatic system is a network of lymph vessels (or lymphoid) that exist throughout the body that connect the lymph nodes. The clear fluid inside the lymphatic vessels, called lymph, contains by-products of tissue and waste, as well as cells from the immune system. Lymph vessels carry the lymph fluid away from the breast. In the case of breast cancer, cancer cells can enter these lymph vessels and begin to grow in the lymph nodes.
Most of the lymphatic vessels drain into the breast to:
- Lymph nodes under the arm (axillary nodes)
- Lymph nodes around the collarbone (above the collarbone) and below the collarbone [subclavian] lymph nodes)
- Lymph nodes inside the chest near the sternum (internal mammary lymph nodes)
If the cancer cells spread to the lymph nodes, there is a greater chance that the cells will travel through the lymphatic system and spread (metastasize) to other parts of the body. The more lymph nodes that contain breast cancer cells, the more likely it is that cancer will be detected in other organs. For this reason, finding cancer in one or more lymph nodes often affects your treatment plan. Generally, you will need surgery to remove one or more lymph nodes and determine if the cancer has spread
However, not all women with cancer cells in the lymph nodes develop their metastases, and some women without cancerous cells develop later in the metastases.