Breast Cancer

Breast cancer is a prevalent disease that affects millions of people worldwide. It occurs when cells in the breast grow uncontrollably, forming tumours that can spread to other parts of the body if left untreated. While breast cancer is more common in women, it can also occur in men. In this article, we will explore the different types, stages and treatment options of breast cancer.

What is Breast Cancer?

Breast cancer develops when cells in the breast undergo abnormal changes and begin to multiply uncontrollably. These cancerous cells can form tumours that may be felt as lumps or thickening in the breast tissue. Breast cancer can also cause changes in the appearance of the breast, such as dimpling, redness, or changes in the nipple. If left untreated, breast cancer cells can spread (metastasise) to other parts of the body, such as the lymph nodes, bones, liver, or lungs, making it more difficult to treat. 

There are several types of breast cancer, each with its own characteristics and treatment options. The most common types include (WHO, n.d): 

• Invasive (infiltrating) ductal carcinoma (IDC): This is the most common type of breast cancer. IDC starts in the milk ducts and invades the surrounding breast tissue. It can spread to nearby lymph nodes and other parts of the body if left untreated.
• Lobular breast cancer: Lobular neoplasia includes lobular carcinoma in situ (LCIS), which is a marker of increased risk rather than true invasive cancer, and invasive lobular carcinoma (ILC), which is a malignant cancer.
• Ductal carcinoma in situ (DCIS): DCIS is a non-invasive breast cancer where the abnormal cells are confined to the milk ducts and have not spread to the surrounding breast tissue.
• Triple-negative breast cancer (TNBC): TNBC is a more aggressive type of breast cancer that lacks oestrogen receptors, progesterone receptors, and excess HER2 protein. It is more difficult to treat than other types of breast cancer.
• Inflammatory breast cancer (IBC): IBC is a rare and aggressive form of breast cancer that causes the breast to appear red, swollen, and inflamed.
• Paget's disease of the breast: This is a rare type of breast cancer that affects the skin of the nipple and areola.

Breast cancers can also be classified based on the presence or absence of specific receptors on the surface of the cancer cells. These subtypes include:

• ER-positive (ER+) breast cancers: These cancers have oestrogen receptors and can be treated with hormone therapy.
• PR-positive (PR+) breast cancers: These cancers have progesterone receptors and can also be treated with hormone therapy.
• HR-positive (HR+) breast cancers: These cancers are either ER+ or PR+ or both.
• HR-negative (HR-) breast cancers: These cancers lack both oestrogen and progesterone receptors.
• HER2-positive (HER2+) breast cancers: These cancers have an excess of HER2 protein and can be treated with targeted therapy.

The early signs of breast cancer include:

• A new lump or thickening in the breast or underarm area
• Changes in the size or shape of the breast
• Dimpling or puckering of the skin
• A nipple that turns inward
• Redness or flaking of the breast skin
• Nipple discharge other than breast milk
• Pain in any part of the breast or nipple area

Breast cancer can present with various symptoms, some of which may be subtle in the early stages. Some common symptoms include:

• New lump or thickening: A new lump or thickening in or near the breast or in the armpit area. The lump may be painless and hard with irregular edges.
• Changes in the breast or nipple: Changes in the size, shape, or texture of the breast, including dimpling, redness, flaking, or thickening of the breast skin, are potential symptoms.
• Nipple changes: Nipple tenderness, inversion, or discharge (other than breast milk), especially if it is bloody, clear, or occurs in only one breast, should be assessed.
• Skin changes: Irritation, dimpling, or changes in the skin of the breast, such as a texture resembling an orange peel, are signs that need attention.
• Pain: Pain in any part of the breast or nipple area can be a symptom, though not all breast cancers cause pain.
• Swollen lymph nodes: Swelling under the arm or near the collarbone can indicate that breast cancer has spread to the lymph nodes.

Breast cancer is staged based on the size of the tumour, the extent of its spread to nearby lymph nodes, and whether it has metastasised to other parts of the body. The stages include (Breast Cancer Staging, n.d.): 

• Stage 0: Stage 0 breast cancer, also known as ductal carcinoma in situ (DCIS), is a non-invasive cancer where the abnormal cells are confined to the lining of the milk ducts. The cancer cells have not spread to nearby breast tissue or lymph nodes.
• Stage 1: In stage 1 breast cancer, the tumour is small (less than 2 cm) and has not spread to the lymph nodes. Stage 1 is divided into two sub-stages:
  • Stage 1A: The tumour is 2 cm or smaller and has not spread to the lymph nodes.
  • Stage 1B: Small clusters of cancer cells are found in the lymph nodes, and either no tumour is found in the breast, or the tumour is 2 cm or smaller.
• Stage 2: Stage 2 breast cancer is divided into two sub-stages:
  • Stage 2A: The tumour is either less than 2 cm and has spread to 1-3 axillary lymph nodes, or the tumour is between 2-5 cm and has not spread to the lymph nodes.
  • Stage 2B: The tumour is between 2-5 cm and has spread to 1-3 axillary lymph nodes, or the tumour is larger than 5 cm but has not spread to the lymph nodes.
• Stage 3: Stage 3 breast cancer is considered locally advanced cancer and is divided into three sub-stages:
  • Stage 3A: The tumour is any size and has spread to 4–9 axillary lymph nodes or has enlarged the internal mammary lymph nodes. It can also be larger than 5 cm and has spread to 1-3 axillary lymph nodes.
  • Stage 3B: The tumour has spread to the chest wall or skin and may have spread to up to 9 axillary lymph nodes or enlarged the internal mammary lymph nodes.
  • Stage 3C: The tumour has spread to 10 or more axillary lymph nodes, lymph nodes near the collarbone, or internal mammary lymph nodes.
• Stage 4: Stage 4 breast cancer, also known as metastatic breast cancer, is when the cancer has spread to other parts of the body, such as the bones, lungs, liver, or brain.

Breast cancer occurs when the cells in the breast grow and multiply abnormally, forming a tumour. Several factors can contribute to the development of breast cancer, including:

• Genetic mutations: Inherited mutations in the BRCA1 and BRCA2 genes significantly increase the risk of breast cancer. Normally, these genes produce proteins that prevent abnormal cell growth, but mutations compromise their protective function.
• Hormonal factors: Long-term exposure to oestrogen, a female hormone, can elevate breast cancer risk. Factors influencing this exposure include early menstruation, late menopause, not having children or having them later in life, and specific hormone replacement therapies.
• Lifestyle factors: Being overweight or obese, lack of physical activity, alcohol consumption, and smoking have all been linked to an increased risk of breast cancer.

Certain factors that increase your risk of developing breast cancer include:

• Women
• Age (over 50)
• Personal history of breast conditions (e.g., lobular carcinoma in situ (LCIS) or atypical hyperplasia of the breast)
• Personal history of breast cancer
• Family history of breast cancer
• Certain gene mutations, such as BRCA1 and BRCA2
• Exposure to radiation
• Obesity
• Beginning your period at a younger age
• Beginning menopause at an older age
• First full-term pregnancy at an older age
• Being nulliparity or who has never given birth
• Postmenopausal hormone therapy
• Excessive alcohol consumption

Breast cancer can spread to other parts of the body, leading to various complications. Some of these complications include:

• Bone complications: When breast cancer spreads to the bones, it can cause bone pain, thinning and weakening of the bones, and an increased risk of fractures.
• Spinal compression: Cancer cells growing in or near the spine can put pressure on the spinal cord, causing back or neck pain, numbness, tingling, and difficulty walking. This can also lead to loss of control over bowel movements or urination.
• Liver complications: Cancer cells in the liver can cause symptoms such as pain or fullness in the stomach, sudden weight loss, vomiting, jaundice, and blockage of bile ducts.
• Lung complications: This can lead to pleural effusion (fluid accumulation around the lungs), causing chest pressure, shortness of breath, and coughing.
• Brain complications: Cancer spreading to the brain can cause headaches, dizziness, nausea, vomiting, seizures, and changes in vision, memory, and behaviour.
• Blood clots: Metastatic breast cancer and some treatments can increase the risk of blood clots.
• Pain and muscle aches: Cancer or treatments can cause pain, muscle and joint aches, and nerve damage.
• Hypercalcemia: Elevated calcium levels in the blood due to bone metastases, leading to symptoms like confusion, lethargy, and muscle weakness.
• Chemotherapy: Common side effects include hair loss, mouth sores, fatigue, loss of appetite, nausea, vomiting, diarrhoea, nail changes, easy bruising, neuropathy, and increased risk of infection.
• Radiation therapy: Common side effects include fatigue, breast soreness, swelling, skin irritation, and potential lymphedema.
• Hormone therapy: Common side effects include hot flashes, vaginal dryness, night sweats, muscle and joint pain, osteoporosis, weight gain, headaches, nausea, fatigue, and mood swings.

While there is no guaranteed way to prevent breast cancer, there are several steps you can take to reduce your risk, including:

• Maintain a healthy weight: Being overweight or obese, especially after menopause, can increase your risk of breast cancer. Aim to maintain a healthy body mass index (BMI) through a balanced diet and regular exercise.
• Exercise regularly: Engage in at least 150 minutes of moderate-intensity or 75 minutes of vigorous-intensity aerobic activity per week, along with strength training exercises at least twice a week.
• Limit alcohol consumption: Drinking alcohol can increase your risk of breast cancer. If you choose to drink, limit your intake to one drink per day or less.
• Avoid smoking: Smoking has been linked to an increased risk of breast cancer, particularly in premenopausal women.
• Hormonal therapy: For women at high risk of breast cancer, such as those with a strong family history or specific genetic mutations, hormonal treatment (e.g., tamoxifen or raloxifene) may be recommended to reduce their risk.
• Preventive surgery: In some cases, women with a very high risk of breast cancer may choose to undergo a prophylactic mastectomy (surgical removal of the breasts) to reduce their risk.
• Regular screenings: Follow recommended screening guidelines for mammograms and clinical breast exams based on your age and risk factors.
• Breast self-exams: Familiarise yourself with your breasts and report any changes or abnormalities to your doctor promptly.

If you notice any signs or symptoms of breast cancer, several diagnostic tests and procedures may be used to identify breast cancer. These include:

• Breast exam: Your doctor will physically examine your breasts, underarms, and collarbone area for any lumps, thickening, or other abnormalities. They will also check for skin changes and nipple discharge.
• Mammogram: This low-dose X-ray of the breast can detect tumours and other abnormalities that may be too small to feel during a physical exam.
• Ultrasound: This test uses sound waves to create images of the inside of your breast. It can help distinguish between solid masses (which may be cancerous) and fluid-filled cysts (which are usually benign).
• Magnetic Resonance Imaging (MRI): An MRI uses magnetic fields and radio waves to create detailed images of the breast. It may be recommended for women with a high risk of breast cancer or to further evaluate abnormalities found on a mammogram or ultrasound.
• Biopsy: If a suspicious area is found during an imaging test, a biopsy may be performed to remove a small sample of tissue for laboratory analysis. There are several types of biopsies. The biopsy sample will be analysed under a microscope to determine if the cells are cancerous and, if so, the type and grade of the cancer. Additional tests, such as hormone receptor and HER2 status tests, may also be performed on the sample to help guide treatment decisions.
  • Fine needle aspiration: Uses a thin needle to remove cells from a suspicious area.
  • Core needle biopsy: Uses a larger needle to remove a small cylinder of tissue.
  • Surgical biopsy: Removes all or part of a suspicious lump for testing.

Once a diagnosis of breast cancer is confirmed, further tests, such as a chest X-ray, computed tomography (CT) scan, bone scan, or positron emission tomography (PET) scan, may be ordered to determine if the cancer has spread to other parts of the body (metastasised).

The primary aim of treating breast cancer is to eliminate cancer cells, prevent recurrence, manage symptoms, and preserve quality of life. Treatment often involves a combination of systemic therapies and surgical interventions specific to the cancer’s type, stage, and receptor status. Early and continuous management significantly improves outcomes and survival rates. Below are the key treatments for breast cancer.

1. Chemotherapy Agents

Chemotherapy is used selectively depending on tumour biology, stage, genomic testing, and recurrence risk. These medications are commonly administered before or after surgery to reduce tumour size, destroy remaining cancer cells, or manage advanced disease (Chemotherapy for Breast Cancer, n.d.). 

• Anthracyclines
  • Doxorubicin, Epirubicin: Interfere with DNA replication to disrupt tumour growth and promote cancer cell death.
• Taxanes
  • Paclitaxel, Docetaxel: Stabilise microtubules and inhibit cancer cell division, often used sequentially with anthracyclines for enhanced efficacy.
• Aromatase Inhibitors
  • Anastrozole, Letrozole, Exemestane: Used in postmenopausal women to block oestrogen production, slowing hormone receptor-positive breast cancer progression.
• Platinum Coordination Complexes
  • Cisplatin, Carboplatin: Cause DNA damage via crosslinking, particularly effective in aggressive or triple-negative breast cancer types.
• Antimetabolites
  • Fluorouracil, Capecitabine, Methotrexate: Mimic DNA components to disrupt synthesis and inhibit the rapid proliferation of malignant cells.
• Alkylating Agents – Nitrogen Mustards
  • Cyclophosphamide: A key component in breast cancer treatments, damaging cancer cell DNA and preventing further replication.

Chemotherapy helps to:

• Shrink tumours before surgery (neoadjuvant therapy)
• Destroy any remaining cancer cells post-surgery (adjuvant therapy)
• Slow disease progression in metastatic stages
• Reduce recurrence and improve long-term survival

2. Surgical Interventions

Surgery helps to remove the primary tumour and affected tissues, and prevents further local spread. It is often combined with chemotherapy for comprehensive care.

• Lumpectomy: Removal of the tumour along with a margin of healthy tissue, preserving most of the breast.
• Mastectomy: Complete removal of one or both breasts to eliminate or prevent cancer spread, especially in advanced or high-risk cases.
• Sentinel Node Biopsy: A diagnostic and therapeutic procedure to assess whether cancer has spread to the lymph nodes.

3. Radiation Therapy

Radiation is used after surgery to target residual cancer cells and reduce the risk of local recurrence. It destroys microscopic cancer remnants, enhances survival post-surgery, and minimises the likelihood of cancer returning in the breast or chest wall.

Living with breast cancer can be challenging, but there are several ways to manage the physical, emotional, and practical aspects of the disease. These include:

• Seek support from family, friends, or support groups. Sharing your feelings and experiences can help you cope better.
• Maintain a healthy lifestyle, including a balanced diet, regular exercise, and adequate rest. Consult your doctor about safe physical activities during and after treatment.
• Attend all follow-up appointments and adhere to the prescribed treatment plan. Regular check-ups can help detect any recurrence early.
• Communicate openly with your healthcare team about any side effects, concerns, or questions you may have.
• Consider seeking professional counselling or therapy to help manage the emotional impact of cancer.
• Explore stress-reduction techniques, such as meditation, deep breathing, or yoga, to promote relaxation and well-being.
• Be patient with yourself and allow time for healing and recovery. Acknowledge that some days may be more challenging than others.

It's essential to be aware of the early signs and symptoms of breast cancer, as early detection can significantly improve the chances of successful treatment. See a doctor if you notice any of the following:

• A new lump or mass in the breast or underarm
• Swelling of all or part of the breast
• Skin dimpling or irritation
• Breast or nipple pain
• Nipple retraction (turning inward)
• Redness, scaliness, or thickening of the nipple or breast skin
• Nipple discharge (other than breast milk)

Remember, these symptoms can also be caused by benign conditions. However, it's crucial to have any new breast change evaluated by a doctor. Early detection is key to successful treatment and improved outcomes in breast cancer.

• Breast cancer treatment typically involves a combination of surgery, radiation therapy, and systemic therapy tailored to the individual patient's needs and the characteristics of the cancer.
• Early detection through regular self-exams and mammograms is crucial for improving breast cancer prognosis.
• Risk factors for breast cancer include age, family history, genetic mutations, and certain lifestyle factors.
• Living with breast cancer can be challenging, but a supportive network, healthy lifestyle, and open communication with doctors can help manage the physical and emotional aspects of the disease.
• Be aware of the early signs and symptoms of breast cancer, and consult a doctor if you notice any changes in your breasts.