Cancer is caused when cells begin to grow abnormally, i.e. out-of-control growth, unlike normal cells that grow, divide, and eventually die. The cancerous cell growth is different from normal cell growth in that the cells continue growing and forming new abnormal cells. They may also invade healthy tissues, making them cancerous.
Breast cancer is a malignant growth in the cells of the breast that can invade surrounding healthy tissue or spread to other parts of the body. Although breast cancer is generally thought to be a woman’s disease, men can get breast cancer too.
Structure of the Breast
The female breast consists of lobules or milk-producing glands, ducts that carry milk from the lobule to the nipple, and stroma surrounding the ducts and lobules. Breast cancer generally begins in the cells lining the ducts (ductal cancer), or in the lobular cells (lobular cancer).
The Lymph System
The lymph system plays an important part in the spread of breast cancer to other parts of the body. Bean-shaped lymph nodes are collections of cells that fight infections, which are connected by lymphatic vessels. These vessels carry clear lymph fluid away from the breast. The lymph contains waste products and immune system cells. When breast cancer cells enter lymphatic cells, they begin to grow in lymph nodes.
Benign Breast Lumps
Oftentimes, breast lumps are not malignant, but benign. Fibrocystic changes of the breast result in the formation of fibrous tissue and fluid-filled cysts. These changes in the breast can cause breast swelling and pain. Other benign breast lumps are fibroadenomas or intraductal papillomas that are not a threat.
Common Breast Cancer Terminology
When a reference to breast cancer is made, you hear specific terms like carcinoma, adenocarcinoma, etc. A few of the terms are explained below:
- Carcinoma – begins in the lining of organs (epithelial cells) like breast. Most breast cancers are carcinoma, ductal or lobular carcinoma.
- Adenocarcinoma – begins in the glandular tissue that is capable of producing and secreting a substance. Breast lobules and ducts are glandular, and cancer of these areas is referred to as adenocarcinoma.
- Carcinoma in situ – refers to early stage of cancer when the cancer is confined to the cells where it started, and is called non-invasive breast cancer.
- Invasive carcinoma – refers to cancer that has grown beyond the cells where it originated.
- Malignant- refers to cancer cells that have the ability to spread to other sites in the body (metastasize) or to overrun and destroy tissues. Due to alterations in their genetic makeup, these cells tend to have fast, uncontrolled growth.