October is breast cancer awareness month, and people are wearing pink to raise awareness of breast cancer, and to raise money for further research and treatment of the disease.
Breast cancer is the second most common cancer to affect American women (skin cancer is the most common). However worldwide, breast cancer is the most common cancer in females.
National Breast Cancer Foundation Inc, 2019 at: https://www.nationalbreastcancer.org/breast-cancer-facts
Men can also get breast cancer. The incidence is much rarer in men than in women, at a rate of around 1 in 1,000 American men.
Although not all of the causes of breast cancer are clear, the most significant risk factor is age, with 80% of all female cancers being diagnosed after age 50 years, and age 60 years in males. Other risk factors are known to be having a family history of the disease, drinking alcohol, being overweight, and taking the combined contraceptive pill and hormone replacement therapy.
The first symptoms of breast cancer usually appear as an area of thickened tissue in the breast or a lump in the breast or an armpit.
Other symptoms include:
- pain in the armpits or breast that does not change with the monthly cycle
- pitting or redness of the skin of the breast, similar to the surface of an orange
- a rash around or on one of the nipples
- discharge from a nipple, possibly containing blood
- a sunken or inverted nipple
- a change in the size or shape of the breast
- peeling, flaking, or scaling of the skin on the breast or nipple
Most breast lumps are not cancerous. However, women should visit a doctor for an examination if they notice a lump on the breast.
Staging of breast cancer is done by using information about the tumour size and location, lymph node involvement, and metastases. There are stages 0 to 4, with some sub groups within these grades. Here is a brief overview of each stage and sub group.
Stage 0: Stage zero (0) describes disease that is only in the ducts of the breast tissue and has not spread to the surrounding tissue of the breast. It is also called non-invasive cancer
Stage 1A: The tumor is small, invasive, and has not spread to the lymph nodes
Stage 1B: Cancer has spread to the lymph nodes and the cancer in the lymph node is larger than 0.2 mm but less than 2 mm in size. There is either no evidence of a tumor in the breast or the tumor in the breast is 20 mm or smaller
Stage 2A: Any 1 of these conditions:
- There is no evidence of a tumor in the breast, but the cancer has spread to 1 to 3 axillary lymph nodes. It has not spread to distant parts of the body
- The tumor is 20 mm or smaller and has spread to the axillary lymph nodes
- The tumor is larger than 20 mm but not larger than 50 mm and has not spread to the axillary lymph nodes
Stage 2B: Either of these conditions:
- The tumor is larger than 20 mm but not larger than 50 mm and has spread to 1 to 3 axillary lymph nodes
- The tumor is larger than 50 mm but has not spread to the axillary lymph nodes
Stage 3A: The cancer of any size has spread to 4 to 9 axillary lymph nodes or to internal mammary lymph nodes. It has not spread to other parts of the body. Stage IIIA may also be a tumor larger than 50 mm that has spread to 1 to 3 axillary lymph nodes
Stage 3B: The tumor has spread to the chest wall or caused swelling or ulceration of the breast or is diagnosed as inflammatory breast cancer. It may or may not have spread to up to 9 axillary or internal mammary lymph nodes. It has not spread to other parts of the body
Stage 3C: A tumor of any size that has spread to 10 or more axillary lymph nodes, the internal mammary lymph nodes, and/or the lymph nodes under the collarbone. It has not spread to other parts of the body
Stage IV (metastatic): The tumor can be any size and has spread to other organs, such as the bones, lungs, brain, liver, distant lymph nodes, or chest wall. Metastatic cancer found when the cancer is first diagnosed occurs about 6% of the time. More commonly, metastatic breast cancer is found after a previous diagnosis of early breast cancer.
Breast cancer subtypes
There are 3 main subtypes of breast cancer that are determined by doing specific tests on a sample of the tumor. These tests will help your doctor learn more about your cancer and recommend the most effective treatment plan. Testing the tumor sample can find out if the cancer is:
Hormone receptor positive: Breast cancers expressing estrogen receptors (ER) and/or progesterone receptors (PR) are called “hormone receptor positive.” These receptors are proteins found in cells. Tumors that have estrogen receptors are called “ER positive.” Tumors that have progesterone receptors are called “PR positive.” Only 1 of these receptors needs to be positive for a cancer to be called hormone receptor positive. This type of cancer may depend on the hormones estrogen and/or progesterone to grow. Hormone receptor-positive cancers can occur at any age, but are more common in women who have gone through menopause. About 60% to 75% of breast cancers have estrogen and/or progesterone receptors. Cancers without these receptors are called “hormone receptor negative.”
HER2 positive: About 10% to 20% of breast cancers depend on the gene called human epidermal growth factor receptor 2 (HER2) to grow. These cancers are called “HER2 positive” and have many copies of the HER2 gene or high levels of the HER2 protein. These proteins are also called “receptors.” The HER2 gene makes the HER2 protein, which is found on the cancer cells and is important for tumor cell growth. HER2-positive breast cancers grow more quickly. They can also be either hormone receptor positive or hormone receptor negative. Cancers that have no or low levels of the HER2 protein and/or few copies of the HER2 gene are called “HER2 negative.”
Triple negative: If a tumor does not express ER, PR, or HER2, the tumor is called “triple negative.” Triple-negative breast cancer makes up about 15% to 20% of invasive breast cancers. Triple-negative breast cancer seems to be more common among younger women, particularly younger black and Hispanic women. Triple-negative cancer is also more common in women with a mutation in the BRCA1 or BRCA2 genes. Experts recommend that all people with triple-negative breast cancer younger than 60 be tested for BRCA gene mutations.
For more information about treatment options for patients with breast cancer visit: