Worldwide, breast cancer in women is the leading type of cancer, accounting for 25% of all cases. In 2012 it resulted in 1.68 million new cases and 522,000 deaths. It is more common in developed countries and is more than 100 times more common in women than in men. According to American cancer society, breast cancer is the second most diagnosed cancer in the U.S and also the second leading cause of cancer deaths.
Breast cancer is the most frequently occurring cancer in Nigeria. It is most commonly found in premenopausal women in their 5th decade. According to Elima et al the age-standardized incidence rate (ASR) at the Ibadan cancer centre was 52.0 per 100 000 and 64.6 per 100 000 in the Abuja cancer centre.
Causes of Breast Cancer in Women
The cause of breast cancer is unknown. One in 8 women has a lifetime risk of having breast cancer. The chances of having breast cancer increase with age.
Breast cancer is always caused by damage to a cell’s DNA. This then leads to an abnormal proliferation of the damaged cell. Genetic (family history and mutation of BRACA 1&2 genes) and environmental factors (such as obesity, use of oral contraceptives, alcohol) can lead to this cellular damage in a susceptible person
Signs and symptoms
The initial sign of breast cancer is a lump more than 80% of breast cancer cases are discovered when the woman feels a lump. However, about 20% of breast lumps are not cancerous. There also can be significant enlargement of one breast compared to the other. Other signs of breast cancer in women include:
- A change in nipple position
- Nipple inversion
- Abnormal/ bloody discharge
- Swelling in the armpit region
Other symptoms that can occur when metastasis (spread to other parts of the body) are;
- Cough occurs when there is lung involvement
- Jaundice results from liver affectation
- Abdominal distension
- Bone pain which occurs when there is metastasis to the bone
- Loss of consciousness. Seizures can result when there is metastasis to the brain
Diagnosis of Breast Cancer in Women
If a nodule is picked up during a routine mammography, a file needle aspiration of the nodule can be done and the sample sent for histology. Also if it’s a lump that was palpated by the woman, a minor surgery to remove the lump is done and the sample sent to the laboratory for review under a microscope (histology).
Sometimes if on examination the doctor is suspecting metastasis, some other tests will have to be conducted such as CT scan, MRI, liver function test etc.
This depends on the grade and stage of the disease.
Stages of breast cancer
- Stage 0; the cancer cells are still within the milk duct and have not invaded deeper into the surrounding fatty breast tissue.
- Stage 1a; the cancer cell is < 2cm without metastasis to surrounding lymph nodes or structures
- Stage 1b; the cancer cell is < 2cm with tiny metastasis to one or two axillary (underarm) lymph nodes alone.
- Stage IIa; the tumour is 2cm but has spread to three or more underarm lymph nodes and to lymph nodes near the breastbone
- Stage IIb; the tumour is >2cm but <5cm and has spread to both some underarm lymph nodes and lymph nodes near the breastbone or the tumour is >5cm.
- Stage IIIa; the tumour has spread to most of the lymph nodes from the underarm to the nodes under the breastbone.
- Stage IIIb; tumour has spread to the chest wall and skin of the breast
- Stag IIIc; the tumour has spread above and below the collarbone
- Stage IV; the tumour has spread to other parts of the body such as the lungs, bone, liver.
The treatment options include;
- Surgery: This includes; lump removal, mastectomy (breast tissue removal), lymph node removal. This can be used for all stages of the disease.
- Radiotherapy: This can also be done especially for women under 70 years to ensure there is no reoccurrence. It is usually used for stage I.
- Chemotherapy: Certain drugs to kill the cancer cells can be given to you by your doctor. It can be given before or after surgery.
- Hormonal therapy: Some cancer cells are sensitive to hormones (estrogen receptor positive or progesterone receptor positive). Hormone therapy can be the main treatment or used in support with other forms of treatment. Hormone therapy is typically given for at least 5 years.
- Targeted therapy: This is a newer type of cancer treatment that uses drugs or other substances to more precisely identify and attack cancer cells.
Outcomes for breast cancer vary depending on the cancer type, extent of disease, and person’s age. Survival rates in the developed world are high, with between 80% and 90% of those in England and the United States alive for at least 5 years. In developing countries, survival rates are poorer.