Breast Cancer Causes, Types, Diagnosis, and Prognosis
Each year, an estimated 207,090 women and 1,970 men are diagnosed with breast cancer in the United States.
What is Breast Cancer?
There are many types of breast cancer. Most breast cancers originate within two types of cells in the breast:
- Ductal carcinoma begins in the cells that line the milk ducts of the breast. It's the most common type of breast cancer.
- Lobular carcinoma begins in the lobules of the breast, the glands that make milk. It's more often found in both breasts than other types of cancers.
Other types of breast cancer include:
- Breast cancer associated with pregnancy
- Breast cancer in men
- Inflammatory breast cancer
- Paget's disease of the nipple
Stages of Breast Cancer
Staging is the process of examining a cancer and determining how far the abnormal cells have spread. Staging is very important in determining the most effective treatment for breast cancer.
Early Stage Breast Cancer
In early stage breast cancers, the cancer is confined to the breast or lymph nodes near the breast.
Some forms of early stage cancer include:
- Stage I breast cancer — cancer cells have appeared in a duct or lobule and have invaded nearby tissue, but have not spread beyond the breast.
- Stage II breast cancer — the tumor is between 2 and 5cm (three-quarters of an inch to 2 inches) and may have spread to lymph nodes under the arm, or is 5cm (2 inches) but has not spread to lymph nodes under the arm.
- Stage IIIA breast cancer — the tumor has spread to lymph nodes behind the breastbone, but has not grown into the chest or skin.
Treatments for early stage breast cancers may include surgery, chemotherapy, and radiation therapy, or a combination of treatments.
Metastatic Breast Cancer
Metastatic breast cancer starts in the breast and spreads to another part of the body.
Metastasis is often referred to as a secondary cancer. The secondary cancer is the same type of cancer as the primary cancer.
For example, if breast cancer spreads to the bone, the cancer cells in the bone are actually breast cancer cells. The disease is metastatic breast cancer, not bone cancer.
The most common places breast cancer cells spread include the:
There are three ways cancer can spread in the body:
- Through tissue — cancer invades the surrounding normal tissue.
- Through the lymph system — cancer invades the lymph system and travels through the lymph vessels to other places in the body.
- Through the blood — cancer invades the veins and capillaries and travels through the blood to other places in the body.
Risk Factors and Symptoms
It is important to know the risk factors and warning signs of breast cancer.
Risk factors may include:
- Age — your chance of getting breast cancer increases with age
- Personal history — having had breast cancer or noncancerous (benign) breast disease
- Family history — having a mother or sister with breast cancer
- Menstruation history — onset of menstruation at an early age
- Reproductive history — older age at first birth or never having given birth
- Dense breast tissue
- Having a gene mutation
- Treatment with radiation therapy to the breast or chest
- Taking hormones, such as estrogen and progesterone
- Drinking alcohol
Symptoms of breast cancer, particularly in the early stages, are often not acute or intense. But as the tumor grows, it may change how the breast looks and feels.
Symptoms and warning signs may include the following:
- Finding a lump or thickening in or near the breast or in the underarm area
- Change in the size, shape, or texture (dimpling or puckering) of the breast.
- Inverted nipple — a nipple turned inward into the breast
- Discharge, with or without blood, from the nipple
- Scaly, red, or swollen skin on the breast, nipple, or areola
Diagnosing Breast Cancer
Tests and procedures to diagnose breast cancer include:
- Biopsy, minimally invasive breast biopsy, or sentinel node biopsy
- Computer aided detection (CAD)
- Digital mammography
- Estrogen and progesterone receptor tests
- Magnetic resonance imaging (MRI)
More about Breast Cancer