Breast Cancer Staging – Everything You Should Know

Breast cancer is becoming more common around the world. However, besides women, it is rarely seen in men as well. The size of a tumour spreads to lymph nodes when moved to other body areas. Its treatment depends on the cancer stage, which helps to know its severity. Some treatments include chemotherapy, radiation, surgery, hormone balance, and treatments.

An Overview of Breast Cancer

Breast cancer is a condition in which breast cells grow uncontrollably. There are many types of breast cancer. The cells in the breast that become cancerous determine the type of breast cancer. 

Breast cancer can develop in different places in the breast. Lobules, ducts, and connective tissue are the three primary components of a breast. The glands that are responsible for making milk are known as lobules.

The ducts refer to tubelike structures that transport milk from the breast to the nipple. All this is held together by connective tissue made up of fibrous and fatty tissue. It usually starts within the ducts or lobules.

Breast Cancer Staging

Breast cancer has five stages:

• Stage 0 (zero), which refers to non-invasive ductal carcinoma in situ (DCIS);
• Stages I to IV (1–4) are used to diagnose invasive breast cancer

Based on the cancer stage, experts find the best treatment for the patient. Doctors can do staging before or after a patient’s surgery. They use the diagnosis to determine the stage of cancer.

Physical examination, image scanning and other tests help determine the staging. Therefore, doctors cannot do the staging unless they have the results for all the tests. Identifying the stage helps the doctor estimate the prognosis or chances of the patient’s recovery.

There are two types of staging: clinical and pathological. Physical examinations, mammograms, ultrasounds, and MRI scans techniques determine clinical staging before surgery.

The surgery removes breast tissue, and the lymph node determines the pathological stage. The pathology report includes information for the calculation of the breast cancer stage.

For example, it determines if the cancer is restricted to one area of the breast or has moved to the breast’s healthy tissues. The doctor may also recommend blood tests or imaging tests if the cancer is likely to spread. 

Breast Cancer Symptoms

Symptoms of breast cancer vary from person to person. Even some women do not show any signs or symptoms at all. The most common symptom of breast cancer is a new lump or swelling in the breast.

However, not every lump implies the occurrence of breast cancer. Breast cancers can be smooth, circular, sensitive, or painful. They can also be painless and have hard lumps with uneven edges.

A few other symptoms are:

• Swelling of the breast (whole or in part)
• Skin dimpling (sometimes with the appearance of an orange peel)
• Pain in breasts or nipples
• Nipple retraction (turning inward)
• Nipple or breast skin turning red, dry, flaky, or thick
• Nipple discharge
• Swollen lymph nodes beneath the arm or towards the collar bone

TNM System

TNM stands for Tumour, Node, and Metastasis. Physicians use the TNM system to identify the stage of your cancer. However, knowing about the same cancer stage may be difficult unless you undergo surgery.

Tumour (T)

The term ‘tumour’ refers to a tumour’s size (area of cancer). It is a simple version of the T stage’s description.

• TX: TX indicates that physicians cannot determine the size of the tumour.
• TIS (DCIS) is an abbreviation for ductal carcinoma in situ. It’s a kind of breast cancer that isn’t yet invasive. The cancerous cells are contained within the breast ducts and have not yet disseminated to the adjacent tissue.
• T1: Breast tumours are 20 millimetres (mm) or less in diameter. Based on the size of the tumour, there are four substages. T1mi refers to cancer that is less than 1 mm in diameter. T1a refers to tumours greater than 1 mm but less than 5 mm. T1b indicates cancer is more significant than 5 mm but smaller than 10 mm. T1c means tumour greater than 10 mm but smaller than 20 mm.
• T2: The tumour is greater than 20 mm but less than 50 mm in diameter.
• T3: The tumour is more than 50 mm in diameter.
• T4: The tumour belongs to one of the four types. T4a indicates that cancer has reached the chest wall. If cancer has developed into the skin, it is T4b. T4c cancer spreads to the chest wall and skin. T4d is inflammatory breast cancer.

Node (N)

The ‘N’ in the TNM staging system refers to lymph nodes. These tiny, bean-shaped shaped organs aid in preventing infection. Regional lymph nodes are located near the site of cancer’s origin. Such as:

• The axillary lymph nodes are under the arm.
• Lymph nodes present above and below the collarbone
• Internal mammary lymph nodes present under the breastbone
• Distant lymph nodes are in other areas of the body 

The staging is described as: 

• NX: No lymph nodes examined
• N0: First, there is no cancer in the lymph nodes. Second, cancerous spots smaller than 0.2 mm are present.
• N1: The tumour has expanded to 1 to 3 axillary lymph nodes and 1 to 3 internal mammary lymph nodes. Micrometastatic cancer is cancer in a lymph node greater than 0.2 mm lymph node but less than 2 mm (N1mi).
• N2: Cancer progressed to 4 to 9 lymph nodes in the axilla. Alternatively, it may have expanded to the internal mammary lymph nodes instead of axillary lymph nodes.
• N3: Cancer advanced to 10 or more axillary lymph nodes and the lymph nodes below the clavicle or collarbone. It’s also possible to spread to the lymph nodes inside the mammary gland.

Metastasis (M)

The letter ‘M’ in the TNM system denotes if cancer has progressed to other body areas,  a condition known as distant metastasis. This tumour then ceases to be classified as early-stage or locally developed.

• MX: It’s impossible to assess the distant spread
• M0: No indication of distant metastases 
• M0 (i+): No indication of distant metastases on clinical or radiographic examination. Tumour cells not larger than 0.2 mm may be in the blood, bone marrow, or other lymph nodes.
• M1: Signs of metastasis to other body regions, indicating that breast cancer cells have spread to other organs.

Other Tests for Breast Cancer Cells

The physician also uses other information related to your breast cancer. This data aids in determining your stage, prognosis, and treatment approach. These are some of them:

• Hormone receptors for female hormones (estrogen and progesterone)
• HER2 status (human epidermal growth factor receptor 2)
• The grade of the cancer

Physicians also check protein levels in human epidermal growth factor receptor 2 (HER2). In some breast tumours, it is more likely to cause HER2-positive cancer. However, this causes cancer cells to multiply and grow and spread rapidly.

Treatment for Breast Cancer

Depending on the stage of your cancer, doctors select the appropriate treatment after considering various factors.

Treatment is dependent on:

• Your type of cancer
• The location of the cancer
• Additional health issues you’re dealing with
• Stage of breast cancer

Additional factors that may have an impact on treatment include:

• The degree to which your cancer cells have progressed
• Whether or not you’ve gone through menopause

Physicians may use the following treatments:

• Surgery
• Radiotherapy
• Chemotherapy
• Hormone replacement therapy

Bisphosphonates

Bisphosphonates are drugs used to treat osteoporosis. In the case of early breast cancer and menopause, you can take bisphosphonates after menopause.

They help prevent the spread of cancer to the bones. Bisphosphonates drugs may also reduce symptoms such as bone pain in patients with secondary breast cancer.

Conclusion

Breast cancer staging is a complex task. First, your doctor will check for any development of a lump or other abnormality in the breasts to determine the cause and, if necessary, treat it.

Before doctors can decide your exact stage, they consider a variety of possibilities and narrow down to the exact kind. In case of any concerns regarding your stage, talk to your GP or Gynaecologist. Early detection of breast cancer increases your chances of successful treatment.

Frequently Asked Questions (FAQs)

Q: What stage of breast cancer requires mastectomy?

A: If you have more than two tumours in the breast, the doctor may prescribe a mastectomy instead of a lumpectomy and radiotherapy. Mastectomy occurs in the early stage of breast cancer. It helps in removing cancerous tissue and lymph nodes. 

Q: How many rounds of chemo is normal?

A: Chemotherapy consists of 4 to 8 cycles of treatment. A cycle is a period between one round of therapy and the beginning of the next. A break is taken after each therapy session to enable your body to recuperate. This break lets the body deal with side effects like nausea and hair loss. 

Q: What stage is a 1.2 cm breast tumour?

A: The size of a tumour is a critical element of breast cancer staging. It has an impact on a person’s options for treatment and prognosis. The tumours are generally small and easier to cure at the initial stage. For example, under the T1 stage  (including T1a, T1b, and T1c), the cancer is 2 cm or smaller (3/4 inch) in diameter. 

Q: How fast do breast tumours grow?

A: Breast cancer cells divide to grow. However, since cancer cells keep mutating, predicting their development rate can be challenging. Every division requires roughly 1 to 2 months, and a noticeable tumour develops in the body for 2 to 5 years. The more cancer grows, the more likely it will infect adjacent tissues, the lymphatic system, or the circulatory system and move to other organs. 

Q: What are the signs that you have a cancerous lymph node?

A: There are multiple signs of a cancerous lymph node. They include lumps beneath the skin in the neck, under the arms, or near the groin region, fever without infection, excess night sweats, weight loss, itchy skin, etc. 

Q: How are cancer stages determined?

A: Tests will be performed by your healthcare professional to evaluate the degree and seriousness of your cancer. A physician will then issue the assessment number. The higher the value, the wider the spread of cancer. Image scanning, physical exams, and other tests can determine the cancer stage. 

Q: Where is the first place breast cancer usually spreads?

A: Breast cancer is more likely to move initially to the lymph nodes present under your arm. It can also spread to the tissue around your breast, including the chest, collarbone, or lower neck. 

Q: What size is a small breast tumour?

A: At its broadest point, the breast tumour is 20 millimetres (mm) or less. It’s about an inch and a half. 

Q: What is the breast cancer survival rate?

A: As per studies, women with non-metastatic invasive breast cancer had a survival rate of 84%, i.e. ten years. When invasive breast cancer is in the breast, the 5-year survival chance is 99%. This stage of breast cancer is in 65% of women. 

Q: When is a mastectomy needed?

A: Breast cancer stages I or II (early stage) require a mastectomy. It removes cancerous tissue and lymph nodes. If more than two tumours are present in the breast, doctors recommend a mastectomy.