Breast Cancer
Breast cancer is the No. 1 cancer among women in Singapore. Most of us would know someone who has, or has had breast cancer, and with the ongoing media coverage of the condition, women are becoming increasingly aware of the condition. National breast screening programmes, dedicated breast clinics, advances in modern treatment methods together with ongoing research, all play their part in the early detection and successful treatment of breast cancer.
What Is Cancer?
Cells throughout the body are continually being lost and replaced, occuring in a state of balance. If, for some reason, the control mechanisms ensuring this balance become disrupted, a cell may start multiplying out of control - a tumour is then born.
Tumours are classified into whether they are benign or malignant. Benign tumours are those which, whilst growing in a uncontrolled manner, do not spread beyond the confines of their anatomical boundaries. Malignant tumours, on the other hand, are those which have the ability to invade structures and thereby enabling them to spread beyond their anatomical boundaries. They are also able to spread to distant parts of the body by invading the blood and lymphatic systems. The characteristic feature shared by all cancers is that this usual balance between cell loss and cell multiplication is disrupted.
What Are The Risk Factors For Developing Breast Cancer?
There are several risk factors for the development of breast cancer. Some women with one, or even a few risk factors, never go on to develop breast cancer, whilst there are many women with breast cancer who have no apparent risk factors.
The following have been found to increase the risk of developing breast cancer:
• Having had cancer in one breast: this increases 3 to 4 fold, the risk of developing a new breast cancer, unrelated to the first, in the other breast, or in another part of the same breast.
• Getting older: the risk of breast cancer increases with age, the peak incidence occurring in the 55 to 59 age group. Whilst breast cancer predominantly affects older women, it can occur in women under 30 years of age.
• Family history of breast cancer: having a first degree relative (mother, sister or daughter) with breast cancer increases your risk of having breast cancer yourself.
• Predisposing breast conditions: history of certain breast conditions, such as atypical lobular or ductal hyperplasia, and lobar carcinoma in-situ, increases the risk of developing breast cancer.
• Genetics: carriers of alterations of the BRCA1 or BRCA2 genes are at higher risk of developing breast cancer. Women suspected to have genetic risk for breast cancer should undergo genetic risk assessment by a specialist (ideally in a cancer genetics clinic). Women with this BRCA mutation have about a 5 - 10 times increased risk for developing breast cancer compared to women without this mutation. They also tend to present with breast cancer at a much earlier age.
• Being Overweight
• Alcohol intake
• Race: caucasian women have been found to be at slightly higher risk of developing breast cancer than their African-American, Hispanic, Native American and Asian counterparts.
• Presence of other cancers in the family: a positive family history of cancers of the ovaries, uterus, cervix or colon increases the risk of you developing breast cancer.
• Excessive exposure to radiation
• Hormone Replacement Therapy (HRT): long term use of combined oestrogen and progesterone increases the risk of breast cancer.
• Late childbirth: having your first child after the age of 35 or never having children increases your risk of breast cancer.
• Early menarche: if you had your first period before the age of 12 years, your risk is increased.
• Late menopause: if you reach menopause very late, this would also increase your risk of breast cancer.
Myths About Breast Cancer Risk
Myth:
Deodorants and anti-perspirants contain toxins which increase breast cancer risk.
Truth:
There is no evidence that deodorants cause breast cancer.
Myth:
Wearing tight-fitting bras or under-wired bras will cause breast cancer.
Truth:
Tight-fitting bras do not cause breast cancer.
Myth:
Women with larger breasts are at increased risk of developing breast cancer.
Truth:
Obesity does increase breast cancer risk, but breast size alone does not.
Myth:
Breast cancer can be caused by an injury to the breast (such as a fall or knock).
Truth:
There is no such link between breast injury and the development of breast cancer.
What Are The Symptoms Of Breast Cancer?
Breast cancer, in its early stages, usually has no symptoms. As the tumour grows, some of the following symptoms may be noticed:
• Lump in the breast or underarm that does not change in size with your mensus. Lumps due to breast cancer are typically painless.
• Changes in the colour or skin of the breast, areola or nipple (e.g. puckering, dimpling or scaling)
• Change in the nipple, such as retraction (pulled in nipple), itching or burning sensation, or discharge from the nipple.
• A marble-like hardened area under the skin of the breast.
• Change in the size or shape of the breast
What Can Help Decrease The Risk Of Developing Breast Cancer?
A healthy balanced diet, regular exercise, maintaining a healthy weight, and avoiding over-consumption of alcohol, will help decrease the chances of developing breast cancer, along with a host of other diseases. Minimizing the use of Hormone Replacement Therapy to as short a time as possible will also minimize risk.
Having regular screening mammograms will not decrease the risk of developing breast cancer, but it enables the best chance of early detection, where treatment is generally more successful.
Breast Cancer Screening
1. Breast Self-Examination:
Large scale studies have found that breast self-examination (BSE), when used for screening, did not reduce mortality rates from breast cancer. However, it is felt that BSE does improve women's awareness of their own breasts, thus allowing any changes to picked up earlier. BSE also helps improve women's awareness of breast cancer.
There are 2 parts to Breast Self-Examination:
(i) LOOK: Look at your breasts in the mirror to check for any changes. This should be done in various positions, such as leaning forward, holding your arms up in the air and with your hands pushing in on the hips. Compare both breasts.
Look for changes on the skin of the breasts(colour, dimpling, a lump or pulling in). The nipples should also be inspected for retraction, inversion, dryness or ulceration.
(ii) FEEL: Many women find it easier to do this while having a bath, because water and soap make it easier and may enhance detection of lumps. Feel all parts of your breasts with the flat of the palm and fingers, for areas that may be different from the rest (such as a lump, a band of hard tissue or a tender area). Remember to also check under the nipples and up into the armpits.
2. Clinical Breast Examination:
Women who have found any change in their breast/breasts should consult their doctors for a clinical breast examination.
3. Mammography
The basic idea behind breast cancer screening, or any other screening for that matter, is that it allows for detection of the breast cancers before they become large enough to be felt. Early detection and treatment generally results in better treatment outcomes.
Mammography screening is widely accepted as appropriate and beneficial for women above the age of 50. In Singapore, the recommendations by the Ministry of Health for Breast Cancer Screening are as follows:
Asymptomatic women 50 - 69 years
All normal risk, asymptomatic women 50 - 69 years should have screening mammograms only every 2 years.
Asymptomatic women 40 - 49 years
Women aged 40 - 49 years with no significantly increased risk, should discuss the benefits, limitations and potential harms associated with screening with their doctors before making a decision on whether or not to have screening.
Asymptomatic women < 40 years
Normal risk, asymptomatic women under 40 years of age do not require breast screening.
Asymptomatic women > 70 years
Unlike in Western nations, where evidence supports mammographic screening every 2 years in women 70 - 75 years of age, the incidence of breast cancer in this age group among Singaporean women is significantly lower. As such, screening mammography may be less beneficial. Asymptomatic women in this age group should discuss the potential benefits and risks of screening with their doctor.
The following groups of women should consult their doctor about screening for breast cancer:
• Women who have increased genetic risk for cancers i.e. family history of breast cancer
• Women on hormone replacement therapy
• Women with prior breast cancer
• Women with premalignant breast conditions
How Is Breast Cancer Diagnosed?
Many women present to their doctors with breast symptoms which do not turn out to be due to cancer. Common benign conditions of the breast include fibroadenomas and fibrocystic disease of the breast. However, all new breast changes should be evaluated by a doctor.
Doctors generally make the diagnosis of breast cancer by employing what is commonly known as the "Triple Test". As its name suggests, there are three parts to it:
(i) Clinical Examination
(ii) Imaging of the Breast
(ii) Breast Biopsy
(i) Clinical Examination
Breast examination by a doctor involves inspecting and palpation of all 4 quadrants (the breast is typically categorized into 4 parts) of both breasts, the area under the nipples, and under both arms to feel for lymph node enlargement.
(ii) Imaging of the Breast
Mammogram
Mammography is the commonest test used to detect breast cancer. In younger women who tend to have much denser breast tissue, mammograms may be difficult to read and doctors may request for other imaging methods instead.
Benign breast lumps are typically rounded with smooth edges. Cancers, by contrast, usually appear denser with an irregular edge. The surrounding tissue may also be distorted by invading cancer cells. Cancers may also be associated clusters of calcium flecks which show up on mammograms as bright white dots.
Ultrasound
Ultrasound of the breast is a good way to focus on areas of the breast which are of particular concern, such as in a region where a lump is felt. It is also frequently done in younger women with denser breast tissue in whom mammograms may not be suitable.
Magnetic Resonance Imaging (MRI)
MRIs are sometimes used to assist in the screening of women at high risk of breast cancer, obtaining more detailed assessment of an area of particular concern found on mammogram or ultrasound, as well as in the monitoring for recurrence after treatment.
(iii) Breast Biopsy
Fine-Needle Aspiration
Fine-needle aspiration (FNA) involves collecting a small sample of breast tissue using a long, thin needle and a syringe. FNAs are done under local anaesthesia. Mammograms or ultrasounds are often used to help locate the area of concern. Cells aspirated are then sent to a pathology laboratory for staining and interpretation.
Core / Mammotome Biopsy
This is similar to the FNA, however, in this case a much larger needle is used to obtain a "worm" of breast tissue rather than just some cells as in that obtained by an FNA. The core biopsy is also done under local anaesthesia and it gives doctors more breast tissue to work on, increasing the accuracy of diagnosis.
Open Surgical Biopsy
This requires a cut in the skin, in order to remove a sample of the lump, or sometimes, the entire lump. This method, whilst being the most accurate method of differentiating benign from cancerous lesions, is a lot more invasive than the previously discussed methods.
Your breast surgeon will advise you on the most appropriate method for obtaining a biopsy sample for you.
Factors Which Affect Prognosis Of Breast Cancer
Several factors are know to affect the likelihood of successful treatment and the risk of recurrence.
These would include the following:
• The stage of the cancer (size of tumour, whether it has spread to the lymph nodes or to other parts of the body)
• The type of breast cancer (eg. tubular, mucinous, papillary)
• Whether the tumour is hormone receptor (estrogen/progesterone receptors) positive or negative
• Histological grade
• Human epidermal growth factor type 2 receptor (HER2) gene amplification and/or overexpression
• Whether the tumour is a new one or a recurrence
• The age, menopausal status and general health of the woman
Treatment Of Breast Cancer
1. Surgery
Surgery is considered to be the primary treatment of breast cancer and many patients with early breast cancer are cured by surgery alone. Surgery aims to completely remove the tumour, as well as to achieve clear resection margins, in order to reduce the risk of tumour recurrence. Several types of surgery are performed (eg. mastectomy, lumpectomy) but these will not be discussed in this article.
2. Adjuvant Therapy
Adjuvant therapy is designed to treat micrometastatic disease (cancer cells which have escaped the breast and regional lymph nodes, and which have not yet had an established identifiable metastatic focus). It is given after primary therapy to increase the long-term disease-free survival.
Types of adjuvant therapy include chemotherapy, hormonal therapy, radiation therapy and targeted therapy with monoclonal antibodies.
The article above is meant to provide general information and does not replace a doctor's consultation.
Please see your doctor for professional advice.