Overview
Breast cancer, as the name suggests, affects breasts in both men and women. This is one of the most common types of cancer. It occurs when cells of the breast undergo mutation, become cancerous, multiply thereby increasing in numbers and result in formation of tumors.
In breast cancer, cells lining the breast lobules and ducts grow at abnormal, uncontrollable rates.
Types & Sub-types
There are several types of breast cancer are;
- Lobular breast cancer
- Angiosarcoma
- Recurrent breast cancer
- Ductal carcinoma in situ(DCIS)
- Invasive ductal carcinoma(IDC)
- Inflammatory breast cancer(IBC)
- Paget’s disease of the breast
- Triple-negative breast cancer(TNBC)
Sub-types are;
- HER2-positive(HER2+)
- Estrogen receptor positive(ER+)
- Progesterone receptor positive (PR+)
- HR-positive(HR+)
- HR-negative(HR-)
Epidemiology & Statistics
- In the United States, Breast cancer is the second most common type of cancer in women (skin cancer is the commonest). This accounts for about 30% of all new female cancer cases per year.
- It mainly occurs in middle-aged and older women.
- The median age at which diagnosis can be made is 62.
- Risk for cancer development by a woman in the United States is about 13%.
Causes
- The exact causes of most of the breast cancers are not yet known.
- According to expert knowledge, breast cells mutate, become cancerous, divide and multiply to form tumors.
- Some of the factors that increase risk of breast cancer are listed in the next section under Risks.
Risks
Several risk factors increase the likelihood of development of breast cancer;
- Personal history of breast cancer in one breast increases risk of occurrence in the other unaffected breast
- Genetics. Some inherited genetic mutations can cause breast cancer to develop. Examples are BRCA 1 AND BRCA 2 gene mutations.
- Smoking tobacco. Tobacco smoking causes several forms of cancer such as lung cancer. It has also been implicated in development of breast cancer.
- Beginning menopause at an older age such as 55 years old.
- Breast conditions such as atypical hyperplasia of the breast.
- Hormone replacement therapy. HRT is likely to cause breast cancer.
- Sex. Women and individuals assigned female at birth are more likely to develop breast cancer as compared to men and persons assigned male at birth.
- Obesity and Body mass index ranges that are unhealthy, such as class III BMI range.
- Age. 55+ years old.
- Exposure of the chest to radiations, such as radiation therapy.
Signs & Symptoms
- Flattened nipple or nipple that has turned inward
- Peeling or scaling of the skin overlying the breast tissues
- Color of the breast skin turns from normal
- Presence of breast lump or thickened skin region that is different from neighbouring tissue
- Nipple discharge
- Swelling in the armpit
- New breast asymmetry(different shape or size as compared to the other breast)
- Swollen breasts that appear red in color
- Nipple sores
Stages
Stage 0: Non-invasive disease that has not yet spread from the breasts.
Stage I: Cancerous cells exist around the breast tissue.
Stage II: Locally advanced breast cancer stage. Tumor has been formed by the cancerous cells. Small tumor(less than 2 centimeters) has spread to under-arm lymph nodes. If larger(around 5 centimeters) has not spread yet.
Stage III: The cancer has spread to surrounding tissues and nearby lymph nodes.
Stage IV: The cancer metastasizes to other regions such as brain and lungs.
Diagnostic Procedures & Tests
Perform a physical examination. Check for both breasts and lymph nodes above the collar bone and arms.
Diagnostic tests include;
- Immunohistochemistry- this checks for hormone receptors
- Breast biopsy. A breast tissue is picked for examination in a by lab by a pathologist.
- Breast ultrasound. This painless scan utilizes soundwaves to produce a picture of a breast.
- Genetic tests that help to check for breast cancer mutations
- Magnetic resonance imaging (MRI) scan. MRI scans can be used to check extent of metastasis/ spread to other regions of the body.
- Mammogram.
Tumor markers for diagnosis of breast cancer include;
- Alpha feto-protein(AFP)
- CA 15-3 (CA refers to carbohydrate antigen)
- CA 19-9
Treatment & Management
Breast cancer surgeries;
- Mastectomy
- Reconstitution of the breast
- Lumpectomy
Treatments that can be administered alongside surgery include;
- Immunotherapy
- Targeted therapy
- Chemotherapy
- Radiation therapy
- Hormone therapy
Prevention
- Perform regular self-examination.
- Screening.
- Frequent physical activity.
- Consume a healthy diet.
- Breast cancer awareness.