What is Breast Cancer?

Breast cancer is a type of cancer that begins in the cells of the breast. It can occur in both men and women, although it is much more common in women. There are many different types of breast cancer. Infiltrating ductal carcinoma is the most common type of breast cancer (70-80%), followed by infiltrating lobular carcinoma (8%), mixed ductal/lobular carcinoma (7%) and other types (less than 5%). The cancer cells can spread by breaking away from the original tumor and entering blood vessels or lymph vessels, which branch into tissues throughout the body. Early detection through screening techniques is crucial for improving survival rates.

 

Causes of Breast Cancer

The exact cause of breast cancer remains unknown, but certain risk factors have been identified. These include:

• Genetics: Inherited gene mutations such as BRCA1 and BRCA2 increase the risk of breast cancer.
• Hormonal factors: Increased levels of estrogen, as seen in early menstruation, late menopause, and hormone replacement therapy, can elevate the risk.
• Family history: Having close relatives with breast cancer can increase an individual's risk.
• Age: The risk of breast cancer increases with age. In age group 30 to 39 years, the risk of breast cancer is 0.44%. The risk of breast cancer increases to 3.5% in age group 60 years and above.
• Lifestyle factors: Factors such as alcohol consumption, obesity, and lack of physical activity can contribute to the risk.

 

Symptoms of Breast Cancer

Most often, signs and symptoms are not due to cancer, but any time an abnormality is discovered, you should be investigated by a healthcare professional. Common symptoms of breast cancer include:

• Lump in the breast or armpit: A hard lump or mass is often the first sign of breast cancer.
• Changes in breast size or shape: Unexplained swelling especially if on one side only, distortion or asymmetry of the breast
• Skin changes: Such as redness, dimpling, puckering of the breast skin or change in the skin texture (some describe this as similar to an orange peel’s texture)
• Nipple changes: Nipple inversion, discharge, or becomes scaly, red, or swollen or may have ridges or pitting resembling the skin of an orange
• Pain: While breast cancer typically does not cause pain in its early stages, some individuals may experience breast or nipple pain.

 

Diagnosis of Breast Cancer

The early detection greatly increases the chances of successful treatment of breast cancer. Diagnosis typically involves:

• Breast cancer screening: Can detect cancer before signs or symptoms develop. It can help find breast cancer in its earliest and most treatable stage. According to the American Cancer Society, when breast cancer is detected in its localized (early) stage, the 5-year relative survival rate is 99%.
• Mammography: X-ray imaging of the breast to detect abnormalities
• Ultrasound: Sound waves are used to create images of the breast tissue.
• MRI: To assess the size and specific location within the breast.
• Biopsy: Removal of a sample of breast tissue for examination under a microscope to determine if cancer is present.

 

Treatment for Breast Cancer

Treatment for breast cancer depends on various factors, including the type and stage of cancer. Treatment options may include:
 

1. Surgery: Surgery is often the primary treatment for breast cancer and typically involves removing the tumor and surrounding tissue. There are different surgical options depending on the stage and characteristics of the cancer such as lumpectomy, mastectomy, or sentinel lymph node biopsy.
2. Radiation therapy: Radiation therapy is often used after surgery to destroy any remaining cancer cells and reduce the risk of recurrence. Radiation therapy may also be used before surgery to shrink tumors or in cases where surgery is not possible.
3. Chemotherapy: Chemotherapy is recommended for various reasons in breast cancer treatment, including:

• Shrinking tumors before surgery (neoadjuvant chemotherapy)
• Destroying any remaining cancer cells after surgery (adjuvant chemotherapy)
• Treating cancer that has spread to other parts of the body (metastatic breast cancer)

Chemotherapy is generally more effective when multiple drugs are combined. These drugs can be given intravenously or orally, allowing the drugs to circulate throughout the body. Chemotherapy is administered in cycles, typically 2-3 weeks apart, and the specific cycle length depends on the chosen drugs. The total treatment time is usually 3-6 months, although it may be longer for metastatic cancer.
Since chemotherapy drugs can affect the entire body, they can also damage healthy cells, especially those that divide rapidly. The side effects may include hair loss, skin and nail changes, mouth sores, fatigue, nausea, vomiting, loss of appetite, diarrhea, or increased risk of infections due to lowered immunity. These side effects often occur during the initial stages of chemotherapy and usually improve during the rest periods between treatments.

4. Hormone therapy: Hormone therapy is primarily used in hormone receptor-positive breast cancers, where the cancer cells have receptors that respond to estrogen (ER+) or progesterone (PR+) or both (ER/PR+). Common hormone therapies include:

• Selective Estrogen Receptor Modulators (SERMs)

Tamoxifen is SERM which blocks the body’s natural estrogen from attaching to breast cancer cells. It is indicated for the treatment of metastatic breast cancer and adjuvant therapy in early-stage breast cancer with positive estrogen receptors (ER+). Tamoxifen can be administered alone or in combination with other chemotherapy drugs, and can be given to both premenopausal and postmenopausal women. It is in tablet form and must be taken every day, usually for a time period of 5-10 years.
In general, the side effects of tamoxifen are less than chemotherapy. It is similar to some of the symptoms of menopause such as hot flashes, vaginal discharge, vaginal bleeding, nausea or fatigue.

• Aromatase Inhibitors (AIs)Aromatase inhibitors are drugs that reduce the production of estradiol in the body. They are commonly prescribed to postmenopausal women but may be used in combination with ovarian suppression therapies or ablation for premenopausal women. Anastrozole, exemestane, and letrozole are examples of aromatase inhibitors. These drugs are typically taken daily for 5-10 years. Common side effects include hot flashes, nausea, vomiting, and bone or joint pain.

5. Targeted therapy: Targeted therapy is a type of treatment that block the growth of breast cancer cells in specific ways. It is often used in combination with other treatments and is particularly effective in treating HER2-positive breast cancers, which overproduce a protein called HER2 that stimulates the growth of breast cancer cells. There are available in both injection form (such as Trastuzumab, Pertuzumab, and T-DM1) and tablet form (such as Lapatinib).

The duration of treatment can vary based on individual factors. For early-stage breast cancer, adjuvant therapy is typically given for 1 year after surgery to reduce the risk of recurrence. For metastatic or advanced breast cancer, the drug may be used until they remain effective.Common side effects include diarrhea, nausea, vomiting or fatigue. If you are receiving with chemotherapy, you may also experience chemotherapy side effects.

6. Immunotherapy: Immunotherapy helps the immune system recognize and attack cancer cells. While still relatively new in breast cancer treatment, immunotherapy has particularly in triple-negative breast cancer, which lacks hormone receptors and HER2 protein. Examples are Dostarlimab and Pembrolizumab.

Immunotherapy is given as an intravenous infusion every 3 or 6 weeks. Possible side effects include fatigue, weakness, nausea, loss of appetite, constipation, diarrhea, cough, anemia, infusion reactions, and autoimmune reactions.
 
In conclusion, breast cancer is a complex disease that requires a comprehensive approach to treat. It is essential to consult with healthcare professionals to determine the most suitable treatment plan based on individual circumstances and preferences. Early detection and personalized treatment are key to improving outcomes and quality of life for individuals affected by breast cancer.
 
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