Breast cancer occurs when there is abnormal, uncontrollable growth of cells in the breast. These cells grow beyond the normal confines of the breast tissue and can spread into adjacent structures and distant organs. It is the most common malignancy affecting females in the western world (second commonest in developing countries – after cervical cancer). In England and Wales, over 40,000 new cases are diagnosed each year with over 20,000 deaths. Men can also be affected by breast cancer but it is more rare (cf. 260 cases, 68 deaths). Mortality from breast cancer remains high in developing countries due to inadequate screening programmes.
There is no known single cause for breast cancer but there are numerous risk factors. The common denominator for these risk factors is prolonged exposure to excessive oestrogen (the female hormone that promotes the growth of breast cells).
These risk factors include:
*Early menarche (less than 11 years at onset of menses) and late menopause (more than 52 years before cessation of menses)
*Advanced age (mean age of breast cancer was found to be 49years in a Nigerian study)
*Family history (breast, ovarian or colonic cancer in first degree relatives – mother or sister)
*History of breast cancer in a male relative
*History of breast cancer in contralateral breast, especially if there is genetic mutation in genes BRCA1 and BRCA2.
*Late pregnancy (>30years before the first pregnancy carried to term) or no pregnancy at all.
*Use of oral contraceptive
*Use of hormone replacement therapy
*Unhealthy lifestyles such as increased weight gain, sedentary lifestyle, alcohol intake, tobacco smoking etc.
SIGNS AND SYMPTOMS
Most cases of breast cancer remain asymptomatic until they become advanced. A lump usually becomes palpable in the breast at a late stage. However, NOT ALL BREAST LUMPS ARE CANCEROUS. A breast lump can be suspected to be cancerous if it feels hard or irregular, contains solid nodular components or is fixed to the skin or underlying muscle.
Most lumps are painless. Pain occurs in only 5% of cases. Other possible signs of breast cancer include:
*Unusual changes in breast size and shape
*Dimples on the breast skin (orange peal appearance)
*Retraction or inversion of the nipples
*Abnormal nipple discharge – purulent or bloody
*Axillary lump (swelling in the armpit)
*Dilated veins on the breast
*Tethering or ulceration of the breast skin
*Symptoms of spread to other organs, such as lungs (cough, bloody sputum), brain (neurological deficits like stroke, seizures, etc.) or bones (fractures)
Because of its insidious onset, the best way to curb the menace of this deadly disease is through effective screening programmes. This will help to detect it at the early stages, whereby successful treatment can be achieved.
What are the screening modalities available?
-Self breast examination (SBE) : all women in the reproductive age group should learn how to check their breasts at least once every month (just after the menses)
-Clinical breast examination : once in a while (depending on age, presence of risk factors and result of previous examinations) women should have their breasts examined by a physician. Any sign or symptom detected during the SBE should be reported promptly for double-check.
-Radiological tests : includes Ultrasound, Mammography, Magnetic Resonance Imagine, or a combination of these as indicated, depending on the density of the breast tissue and individual risk factor assessment.
A definitive diagnosis is made through biopsy. This could be done through a needle with radiological guidance, to obtain a sample from the lump and send to the laboratory for confirmation. Excisional biopsy can also be done – a surgical procedure whereby the entire lump is removed and sent for laboratory (histological) examination. Other investigations needed to rule out, or confirm metastases, as well as prepare patients for treatment include:
Full blood work up
Renal and liver function tests, etc.
The first level of management is to “stage” the disease. This “staging” provides an idea of how advanced the malignancy is. It also gives us the prognostic indices such as likelihood of cure, remission and recurrence. The popular TNM classification is used to categorise the diseases into stages 0 to IV, where 0 is the earliest stage and IV is the most advanced stage. TNM stands for:
T-clinical staging of breast lump
N-lymph node involvement
M-presence and type of metastasis (local or distant spread)
Treatment depends on the stage. This can either be curative or palliative. There are 3 broad modalities of treatment : Surgery,
Chemotherapy and Radiotherapy. Other classes of treatment are:
A combination of these modalities are often employed. Palliative measures used in advanced cancer include:
-Treatment of metastatic disease
-Home care and end of life support
Breast cancer is a disease of public health importance. Thanks to the aggressive campaign for active screening and early detection, mortality rate has been decreasing steadily in the developed world but this can not be said of the developing countries. We need to do more of public enlightenment and advocacy programmes to augment the effort of the government in preventing and curing this disease.
-NICE guidance, UK, 2016 update
-Medscape reference, Breast Cancer, 2017 update.