BC Basics

Breast cancer is a disease that starts as a growth of cells in the breast tissue.

It is the second-most common type of cancer diagnosed among women in the U.S., after skin cancer. 

Though it mainly occurs in women who are over the age of 50, it can also affect younger women. The average age at diagnosis is about 62 years.

Breast cancer is much more common among women, but it can also affect men since they are also born with a small amount of breast tissue.

Survival rates of breast cancer are increasing thanks to increased awareness, early detection, more funding for research and improved treatments.

What causes Breast Cancer?

The exact cause of breast cancer is not known. However, there are a number of factors that increase the risk of developing it.

These include a family history of breast cancer, certain genetic mutations (such as BRCA1 or BRCA2), a personal history of breast cancer, a personal history of other breast conditions like lobular carcinoma in situ, also called LCIS and atypical hyperplasia of the breast, starting menstrual periods at a younger age or entering menopause at an older age, having your first child at an older age (i.e., after age 30), never having been pregnant, not having breastfed, having a dense breast tissue, alcohol consumption, hormonal therapy, obesity, increased age and radiation exposure.

Smoking has also been linked to an increased risk of breast cancer as with other types of cancer. 

Types of Breast Cancer

There are different types of breast cancer. These include invasive ductal carcinoma (IDC), invasive lobular carcinoma, ductal carcinoma in situ (DCIS), triple-negative breast cancer (TNBC), inflammatory breast cancer (IBC) and Paget’s disease of the breast.

IDC is the most common type of breast cancer in the US in which the cancer starts in the milk ducts and spreads to the nearby tissues.

Lobular breast cancer starts in the lobules, which are the milk-producing glands.

DCI also starts in the milk ducts, but unlike IDC, it does not spread to other parts of the breast tissue.

TNBC is a type of invasive breast cancer that lacks estrogen and progesterone receptors and lacks the HER2 protein, which promotes tumor growth. It is aggressive and spreads more quickly than other types of breast cancer.

IBC is a rare, aggressive form that causes redness, swelling, and skin changes that may resemble a rash or infection.

Finally, Paget’s disease of the breast is also a rare type of breast cancer that affects the skin of the nipple and may look like a rash.

What are the symptoms of Breast Cancer?

The symptoms of breast cancer include a new lump in the breast or armpit, a nipple that is turned inwards, changes in breast skin color or texture like peeling, scaling, crusting or flaking and changes in the overall appearance of the breast, like its size and shape.

In some cases, a blood-stained or clear fluid discharge from the nipple can also be a symptom of BC.

Pain in your breast or armpit that does not go away can also be a symptom and should be checked.

The symptoms of breast cancer that may spread to other parts of the body may include fatigue, loss of appetite, feeling unwell, being sick and having difficulty sleeping. 

How is Breast Cancer diagnosed?

Breast cancer may be suspected after a breast examination by a doctor or if the patient reports symptoms that align with it. In such cases, a diagnostic mammogram and additional tests, such as breast ultrasound or breast magnetic resonance imaging (MRI), may be performed. 

A breast biopsy, where a small sample is taken from the abnormal breast tissue and examined in the laboratory, is required to confirm the diagnosis.

Stages of Breast Cancer

Breast cancer is usually divided into 5 stages, from stage 0 to stage 4. Staging is based on tumor size, lymph nodes, spread, and sometimes tumor biology.

In stage 0, the disease is non-invasive, meaning it has not spread from the milk ducts.

In stage 1, cancerous cells are present and limited to the breast, with little or no lymph node involvement.

In stage 2, the cancerous cells have formed tumors. For breast cancer to be classified as stage 2, these tumors must either be larger than 5 cm in diameter and not spread to the lymph nodes in the armpit or be larger than 2 cm in diameter if they have spread to the armpit.

In stage 3 breast cancer, the cancer has extensively invaded breast tissue and spread to the nearby structures or multiple lymph nodes.

Finally, stage 4 breast cancer refers to metastatic disease that has spread to other organs like the bones, lungs, liver and brain.

Can Breast Cancer be prevented?

Even though breast cancer cannot always be prevented, certain steps can improve early detection and intervention. These include performing self-examinations and undergoing breast cancer screening.

Some lifestyle changes may reduce the risk of developing breast cancer, like reducing or abolishing alcohol consumption, quitting smoking, exercising regularly, limiting hormonal therapy and maintaining a healthy weight

Genetic testing can help identify the risk of breast cancer and help ensure you are regularly checked if you are at risk.

How is Breast Cancer treated?

The main treatment approach for breast cancer is surgery to remove the cancerous tissue. 

There are different types of surgery for breast cancer. These include lumpectomy, which involves the removal of the cancer tissue and some of the healthy tissue around it and a mastectomy, where the entire breast is removed. This can be done to one or both breasts.

If imaging tests show that the cancer has spread to the nearby lymph nodes, a surgery called axillary lymph node dissection can also be performed, in which the lymph nodes in the armpit are removed.

There are other treatments available for breast cancer. These include radiotherapy, chemotherapy and hormone therapy to shrink the cancer. Sometimes, these can be used before surgery to reduce the size of the tumor that will be removed.

Newer treatments also exist for the treatment of breast cancer, like immunotherapy, which involves “training” the immune system to recognize and kill cancer cells, and targeted therapies that target the genetic changes that cause healthy cells to be transformed into cancerous cells.