Breast cancer is cancer that develops in breast cells. It forms in either the lobules or the ducts of the breast, though it can also occur in the fatty tissue or the fibrous connective tissue. In its early stages, breast cancer may not exhibit any symptoms. In many cases, a tumour (cancerous growth) may be too small to be felt, but it will show up on a mammogram. This is why it is important to get regular breast exams yearly and mammograms too above the age of 40, as this is when the risk of breast cancer increases.
Each type of breast cancer exhibits a variety of symptoms. Some of the common ones include:
- a breast lump that was not there before
- breast pain
- red, pitted skin over your entire breast
- swelling in all or part of the breast
- nipple discharge (not breast milk)
- bloody discharge from the nipple
- peeling, scaling or flaking of skin on the nipple or breast
- a sudden, unexplained change in the shape or size of the breast
- inverted nipple
- a lump or swelling under your arm
There are several risk factors that increase the risk of breast cancer. These include:
- Increased age
- Drinking excessive amounts of alcohol
- Genes – women with certain gene mutations are more likely to develop breast cancer
- Early menstruation
- Giving birth at an older age
- Hormone therapy
- Family history
- Late menopause
- Never being pregnant
- Previous breast cancer
Breast cancer is divided into two main categories — invasive and noninvasive (in situ). While invasive cancer spreads from the breast ducts or glands to other parts of the breast, noninvasive cancer does not spread.
- Ductal carcinoma in situ is a noninvasive condition. The cancer is confined to the breast ducts.
- Lobular carcinoma in situ is noninvasive cancer that grows in the milk-producing glands.
- Invasive ductal carcinoma is the most common type of breast cancer. It begins in the milk ducts and further invades nearby breast tissues. It can begin to spread to other nearby organs and tissue.
- Invasive lobular carcinoma first develops in the breast lobules and further invades nearby tissue.
Breast cancer is divided into stages based on how large the tumour is and how far it has spread. There are five main stages — stages 0 to 5.
Stage 0 breast cancer
- Cancer cells are confined to the breast ducts and have not spread into nearby tissue.
Stage 1 breast cancer
- Stage 1A: The primary tumour is 2 centimeters wide or less and the lymph nodes are not affected.
- Stage 1B: Cancer is found in nearby lymph nodes and either there is no tumour in the breast or it is smaller than 2 cm.
Stage 2 breast cancer
- Stage 2A: The tumour is smaller than 2 cm and has spread to 1–3 nearby lymph nodes, or it is between 2 and 5 cm and has not spread to any lymph nodes.
- Stage 2B: The tumour is between 2 and 5 cm and has spread to 1–3 axillary (armpit) lymph nodes, or it is larger than 5 cm and has not spread to any lymph nodes.
Stage 3 breast cancer
- Stage 3A: The cancer has spread to 4–9 axillary lymph nodes or the tumour is greater than 5 cm and the cancer has spread to 1–3 axillary lymph nodes or any breastbone nodes.
- Stage 3B: A tumour has invaded the chest wall or skin and may or may not have invaded up to 9 lymph nodes.
- Stage 3C: Cancer is found in 10 or more axillary lymph nodes, lymph nodes near the collarbone, or internal mammary nodes.
Stage 4 breast cancer
- This stage can have a tumour of any size and its cancer cells have spread to nearby and distant lymph nodes as well as distant organs.
The first step to diagnose breast cancer is to perform a thorough physical exam as well as a breast exam. This might be followed by a mammogram and/or an ultrasound. Annual mammograms are suggested for women above the age of 40 years to preemptively spot and treat any tumours. If there is an abnormal growth in the breast tissue, a breast biopsy is suggested. A small tissue sample is taken from the suspicious area and tested.
Based on the stage of cancer, the modality of breast cancer treatment may vary. Surgery is the most common treatment for breast cancer. Additional treatments, such as chemotherapy, targetted therapy, radiation or hormone therapy are suggested thereafter to minimise the change of regrowth.
Several types of surgery may be used to remove breast cancer, including:
- Lumpectomy, where the tumour and some surrounding tissue is removed, leaving the rest of the breast intact.
- Mastectomy, where the entire breast is removed.
- Sentinel node biopsy, where a few lymph nodes that receive drainage from the tumour are removed.
- Axillary lymph node dissection, where additional lymph nodes are removed if the sentinel node biopsy indicates cancer.
- Contralateral prophylactic mastectomy, where even though cancer may be present in only breast, the healthy breast is removed (elective) to reduce the risk of developing breast cancer again.
While there are risk factors one cannot control, there are certain ways one can reduce the risk of developing breast cancer.
Lifestyle can affect one’s risk of breast cancer. Maintaining a healthy diet and getting more exercise could lower the risk. Limiting the intake of alcohol and quitting smoking are also suggested.
Regular Breast Screening
Meeting a gynaecologist is not limited to only the childbearing years of a woman’s life. It is advised to get regular breast screening and an annual mammogram done after the age of 40. Self-examination of the breast is also recommended on a regular basis as no one knows your body better than you. The exam can help one become familiar with one’s breasts so that you are able to immediately identify when there is even a small change.
Some women are at increased risk of breast cancer due to hereditary factors. Talk to the doctor about preemptive treatment options.