Health Resources

Breast Cancer

What is Breast Cancer

​Breast cancer is a cancer that forms in breast cells. It usually originates through the mutation of cells in the lining of the milk ducts and lobules in the breasts. It is the most common cancer in women and it can occur in men too. There are 2 broad types of cancer; the non-invasive breast cancer and invasive breast cancer. 

The non-invasive breast cancer cells are contained within the milk ducts. However, if left untreated, the cancer cells can break out of the milk ducts and spread out, thus becoming an invasive breast cancer.

The invasive breast cancer cells spread outside the milk ducts or the lobules. These cancer cells will first spread to the surrounding breast tissue, move into the lymph nodes or blood stream and then travel to other parts of the body. The most common parts that the cancer cells travel to are the lungs, liver and bone.
Causes of the condition

​The exact cause remains unknown. However, it is known that cancer occurs when the breast cells begin to grow abnormally and multiply more rapidly than healthy cells. The accumulating cells form a tumour.

Signs & symptoms

Thickening that feels different from surrounding tissue in other parts of the breast

  • Breast lump or swell in the underarm (armpit) area
  • Bloody discharge from nipple
  • Change in shape or size of the breast
  • Changes to the skin over the breast such as dimpling
  • Inverted nipple
  • Peeling or flaking of the nipple skin
  • Redness or flaky skin over breast
Diagnosis and treatment options

​Test and diagnosis

  • Clinical breast examination
  • Mammogram
  • Breast ultrasound
  • Breast magnetic resonance imaging (MRI)
  • Core biopsy


There has been a vast improvement in the treatment options available today for breast cancer. In the past, the gold standard was a mastectomy, which is the removal of the whole breast. Today, breast conservation surgery is a viable option for most cancers, but must be followed by radiotherapy. There are also a vast variety of reconstructive options. After surgery, most women will require chemotherapy, after which, if suitable, they will be prescribed medication (usually Tamoxifen) for five years.
Mastectomy is the removal of all tissue from the breast with the cancer. It is usually performed if the cancerous lump is large in proportion to the breast or the cancer cells are present in many areas of the breast. This surgery ensures that all breast tissue that can be removed will be removed and the need for radiotherapy after this operation is less than 5%.

Lumpectomy surgery is a partial mastectomy surgery. It removes the breast cancer and some of the surrounding tissues.

Radiation therapy is the use of high energy radiation to kill cancer cells within the treated area. Radiation therapy is used after the surgery to destroy any cancer cells remaining in the breast.

Chemotherapy is the use of drugs to kill the cancer cells which may have escaped from the original tumour. These drugs may be taken orally or injected into the vein. These drugs enter into the bloodstream, travel through the whole body and it can destroy cancer cells throughout the body. Besides destroying cancer cells, chemotherapy may also affect normal cells.

Hormone therapy is used to block the hormone receptors, preventing the hormones from getting to the tumours and thus stopping the growth of the tumour. These are usually in the form of tablets, namely Tamoxifen or newer options such as aromatase inhibitors.

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