The staging system most often used for breast cancer is based on 3 factors:
- T: The extent of the primary tumor (T)
- N: Has cancer spread to nearby lymph nodes (N)
- M: Has the cancer spread (metastasized – M) to different sites
Stage I
- The tumor is less than 2 cm (0.8 inches) in size that is node-negative
Stage II
- Tumors have spread to the axillary (armpit) lymph nodes and/or a tumor size larger than 2 cm but smaller than 5 cm (about 2 inches)
Stage III
- Large breast tumors (greater than 5 cm, or about 2 inches, across),
- Extensive axillary (armpit) nodal involvement (more than 10 lymph nodes with cancer)
- Lymph node involvement of both axillary and internal mammary nodes (behind the ribs of the breast with cancer) at diagnosis
- Nodal involvement of the soft tissues above or below the collarbone
- Or, the tumor extends to the underlying muscles of the chest wall or the overlying skin
- Inflammatory breast cancer, a fast-growing type that causes the breast to appear red and swollen, is at least stage III, even if it is small and does not involve lymph nodes
Stage IV – metastatic breast cancer
- Tumors have spread (metastasized) to areas outside the breast and lymph nodes to the bones, lungs, liver, or other organs
- The primary tumor can be any size, and there may be any number of affected lymph nodes
What Is Breast Cancer?
Breast cancer occurs when abnormal cells in the breast grow out of control. Breast cancer is the most common female cancer in the U.S., and the second-leading cause of cancer death in women (lung cancer is the leading cause of cancer deaths). While breast cancer is more common in women, men can get it too.
What Are Symptoms of Breast Cancer?
Symptoms of breast cancer include:
- New lump in the breast
- Swelling of all or part of the breast
- Skin irritation or dimpling
- Breast pain
- Nipple pain
- Nipple turning inward
- Redness, scaling, flaking, or thickening of the nipple or breast skin
- Nipple discharge that is not breast milk
- A lump in the armpit
- A change in the size or the shape of the breast
What Causes Breast Cancer?
The specific cause of breast cancer is unknown, but it is a result of damage to a cell’s DNA.
Risk factors for developing breast cancer include:
- Age over 50 years
- Inherited genetic mutations, such as mutation in the BRCA1 and BRCA2 genes
- Family history of breast cancer, especially a first-degree relative (mother, sister, or daughter)
- Personal history of breast cancer or noncancerous breast disease
- Having dense breasts
- Previous radiation therapy treatment to the chest or breasts
- Early onset of menstrual periods (before age 12) or late menopause (after age 55)
- History of use of the drug diethylstilbestrol (DES)
- Physical inactivity/sedentary lifestyle
How Is Breast Cancer Diagnosed?
On physical exam, a healthcare provider may find a lump in the breast. Additional tests will be used to confirm a diagnosis, such as:
- Mammogram
- Breast ultrasound
- Magnetic resonance imaging (MRI) of the breast
- Biopsy
If the breast cancer is suspected of metastasizing imaging studies may be done to determine if the cancer has spread:
- Bone scan
- Computerized tomography (CT) scan of the chest
- CT scan of the abdomen and pelvis
- Positron emission tomography (PET) scan
What Is the Treatment for Breast Cancer?
Treatment for breast cancer depends on the extent of the tumor and may involve one or more of the following:
- Surgery
- Mastectomy: removal of the entire breast. May be followed by breast reconstruction.
- Lumpectomy: removal of the tumor and some healthy tissue that surrounds it
- Radiation therapy
- Chemotherapy
- Hormone therapy
- Targeted therapy
- Immunotherapy
What Are Complications of Breast Cancer?
Complications of advanced breast cancer include:
- Cancer-related fatigue
- Lymphedema
- Ulceration of the skin of the breast
- Bone metastases
- Brain metastases
Complications of breast cancer surgery include:
- Pain
- Infection
- Post-operative bleeding
- Lymphedema
- Cording (axillary web syndrome)
- Limited range of movement in shoulder
- Nerve pain or numbness
- Tissue death (necrosis)
- Change in posture, resulting in neck, back, or shoulder discomfort
- Cosmetic issues with the appearance of the breast
What Is the Life Expectancy for Breast Cancer?
Life expectancy for breast cancer is often expressed in five-year survival rates, that is, how many people will be alive five years after diagnosis.
- The five-year survival rate for localized breast cancer (cancer that has not spread outside the breast) is 99%.
- The five-year survival rate for regional breast cancer (cancer has spread outside the breast to nearby structures or lymph nodes) is 86%.
- The five-year survival rate for distant breast cancer (cancer has spread to distant parts of the body, such as the bones, liver, or lungs) is 27%.
How Do You Prevent Breast Cancer?
Breast cancer may not be able to be prevented. Some risk factors can be managed to reduce the risk of developing breast cancer, such as:
