Breast cancer is cancer that forms in the cells of the breast. Breast cancer can occur in both men and women, but it is far more common in women. It is the most commonly diagnosed cancer after breast cancer, and is the most common cancer in women.
Breasts are made up of fat, connective tissue, and tiny glands known as lobules, that aid milk production. Cancers of the breast may affect any of these systems, but they most commonly arise in these milk-producing ducts (invasive ductal carcinoma). Errors in the DNA of cells in the breast lead to excessive growth and alteration of these cells, leading to tumor formation.
TYPES OF BREAST CANCER
There are several different types of breast cancer, which can develop in different parts of the breast. Breast cancer is often divided into non-invasive and invasive types.
Non-invasive breast cancer
Non-invasive breast cancer is also known as cancer or carcinoma in situ, or pre-cancerous cells. This cancer is found in the ducts of the breast and has not developed the ability to spread outside the breast. This form of cancer rarely shows as a lump in the breast and is usually found on a mammogram. The most common type of non-invasive cancer is ductal carcinoma in situ (DCIS).
Invasive breast cancer
Invasive cancer has the ability to spread outside the breast, although this does not mean it necessarily has spread. The most common form of breast cancer is invasive ductal breast cancer, which develops in the cells that line the breast ducts. Invasive ductal breast cancer accounts for about 80% of all cases of breast cancer and is sometimes called ‘no special type’.
Other types of breast cancer
Other less common types of breast cancer include invasive lobular breast cancer, which develops in the cells that line the milk-producing lobules, inflammatory breast cancer and Paget’s disease of the breast. It is possible for breast cancer to spread to other parts of the body, usually through the lymph nodes (small glands that filter bacteria from the body) or the bloodstream. If this happens, it is known as secondary or metastatic breast cancer.
SIGNS AND SYMPTOMS
Signs and symptoms of breast cancer may include:
- A breast lump or thickening that feels different from the surrounding tissue
- Change in the size, shape or appearance of a breast
- Changes to the skin over the breast, such as dimpling
- A newly inverted nipple
- Peeling, scaling or flaking of the pigmented area of skin surrounding the nipple (areola) or breast skin
- Redness or pitting of the skin over your breast, like the skin of an orange
RISK FACTORS FOR BREAST CANCER:
The exact cause of breast cancer is not known, but environmental and genetic (familial) factors, and age play a strong role. 5-10% of breast cancer mutations are passed down in the family. The most common genetic mutations leading to breast (and ovarian) cancers are BRCA 1 and BRCA 2.
Factors that are associated with an icnreased risk of getting breast cancer are:
Female sex. Women are much more likely to get breast cancer than men.
Increasing age: increase in age also increases the risk of cancer, as genetic mutations are more likely to happen as we advance in age.
Radiation exposure to the chest (X Rays, especially as a child).
Obesity also increases the risk of breast cancer, along with 12 other types of cancer.
Onset of periods (menarche) before the age of 12 years.
Giving birth to your first child after the age of 30 years.
Never being pregnant increases your risk of breast cancer significantly more than women who have given birth.
Drinking alcohol also increases the incidence of breast cancer.
DIAGNOSIS OF BREAST CANCER:
There are multiple diagnostic tools for diagnosing breast cancer.
Breast exam is the first line for detecting any abnormalities in the shape, size or texture of the breast. Regular self exam of breast by patients has not shown to be any more effective in picking up irregularities/early cancer than a yearly check up by your doctor.
Mammogram. A mammogram is an X-ray of the breast. Mammograms are commonly used to screen for breast cancer. If an abnormality is detected on a screening mammogram, your doctor may recommend a diagnostic mammogram to further evaluate that abnormality.
Breast ultrasound. Ultrasound uses sound waves to produce images of structures deep within the body. Ultrasound may be used to determine whether a new breast lump is a solid mass or a fluid-filled cyst. Ultrasound is recommended in patients less than 40 years old.
Removing a sample of breast cells for testing (biopsy). A biopsy is the only definitive way to make a diagnosis of breast cancer. Biopsy samples are sent to a laboratory for analysis where experts determine whether the cells are cancerous. A biopsy sample is also analyzed to determine the type of cells involved in the breast cancer, the aggressiveness (grade) of the cancer, and whether the cancer cells have hormone receptors or other receptors that may influence treatment options.
Breast magnetic resonance imaging (MRI). An MRI machine uses a magnet and radio waves to create pictures of the interior of your breast.
Breast cancer stages range from O to IV with O indicating cancer that is noninvasive or contained within the milk ducts. Stage IV breast cancer, also called metastatic breast cancer, indicates cancer that has spread to other areas of the body.
TREATMENT OF BREAST CANCER
The first type of treatment for breast cancer is usually surgery. The type of surgery depends on the type of breast cancer you have. Surgery is usually followed by chemotherapy or radiotherapy or, in some cases, hormone or biological treatments.
There are two types of surgery for breast cancer. These are surgery to remove just the cancerous lump (tumour), known as breast-conserving surgery, and surgery to remove the whole breast, which is called a mastectomy. In many cases, a mastectomy can be followed by reconstructive surgery to recreate the breast that was removed.
Studies have shown that breast-conserving surgery followed by radiotherapy is as successful as total mastectomy at treating early-stage breast cancer.
Breast reconstruction is surgery to make a new breast shape that looks as much as possible like your other breast. Reconstruction can be carried out at the same time as a mastectomy (immediate reconstruction) or it can be carried out later (delayed reconstruction). It can be done either by inserting a breast implant or by using tissue from another part of your body to create a new breast.
Lymph node surgery
To find out if the cancer has spread, a procedure called a sentinel lymph node biopsy (SLNB) may be carried out. The sentinel lymph nodes are the first lymph nodes that the cancer cells reach if they spread. They are part of the lymph nodes under the arm (axillary lymph nodes).
If there are cancer cells in the sentinel nodes, you may need further surgery to remove more lymph nodes from under the arm.
Radiotherapy uses controlled doses of radiation to kill cancer cells. It is generally given after surgery and chemotherapy to kill any remaining cancer cells.
If you need radiotherapy, your treatment will begin within 12 weeks of your surgery or within a month of your chemotherapy if you receive chemotherapy. Radiotherapy treatment is typically given five days a week and may last for three to five weeks. Each treatment session will only last a few minutes.
The side effects of radiotherapy include:
- The skin inside the area treated with radiotherapy may become red and irritated and occasionally may peel. These effects heal after radiotherapy but the skin colour may be permanently darker or lighter in the treated area.
- fatigue (extreme tiredness)
- lymphoedema (excess fluid build-up in your arm caused by blockage of the lymph nodes under your arm)
- The breast may become tender and sensitive. In the long-term the breast may appear smaller in size and the breast tissue may harden (fibrosis)
Chemotherapy involves using anti-cancer (cytotoxic) drugs to kill the cancer cells. Chemotherapy is usually used after surgery to destroy any cancer cells that have not been removed. This is called adjuvant chemotherapy. In some cases, you may have chemotherapy before surgery, which is generally used to shrink a large tumour. This is called neo-adjuvant chemotherapy.
You may receive chemotherapy sessions once every two to three weeks, over a period of four to eight months, to give your body a rest in between treatments.
The main side effects of chemotherapy are caused by their influence on normal, healthy cells, such as immune cells. Side effects include:
- loss of appetite
- nausea and vomiting
- hair loss
- sore mouth
Chemotherapy drugs can also stop the production of oestrogen in your body. Oestrogen is known to encourage the growth of some breast cancers. If you have not been through the menopause, your periods may stop while you are undergoing chemotherapy treatment.
Some breast cancers are stimulated to grow by the hormones oestrogen or progesterone, which are found naturally in your body. These types of cancer are known as hormone-receptor-positive cancers. Hormone therapy works by lowering the levels of hormones in your body or by stopping their effects.
Hormone therapy may be used as the only treatment for breast cancer if your general health prevents you from having surgery, chemotherapy or radiotherapy.
In most cases, you will need to take hormone therapy for up to five years after your surgery.
Hormone therapy is only effective in hormone-sensitive cancer.
PREVENTING BREAST CANCER:
Diet and lifestyle
Regular exercise and a healthy diet are recommended for all women as they can help prevent many conditions, including heart disease, diabetes and many forms of cancer.
Studies have looked at the link between breast cancer and diet and, although there are no definite conclusions at the moment, there are benefits for women who maintain a healthy weight, do regular exercise and who have a low intake of saturated fat and alcohol.
It has also been suggested that regular exercise can reduce your risk of breast cancer by as much as a third. If you have been through the menopause, it is particularly important that you are not overweight or obese. This is because these conditions cause more oestrogen to be produced, which can increase the risk of breast cancer.
Studies have shown that women who breastfeed are statistically less likely to develop breast cancer than those who do not. The reasons are not fully understood, but it could be because women do not ovulate as regularly while they are breastfeeding and oestrogen levels remain stable.
October is the annual breast cancer awareness month, and PINK is the official breast cancer awareness color. It is often referred to as Pinktober.