Breast cancer is the most common type of cancer among women in Singapore today. 1 out of every 16 women in Singapore is likely to be afflicted by breast cancer, with more than 1,300 new cases diagnosed every year.
Normal cells divide and reproduce
in an orderly manner. Your body
relies on this orderly activity to
repair injuries and replace wornout
tissue. Sometimes this orderly
process is disrupted. Cells grow and
divide out of control, producing
extra tissue to form a mass or lump
called a tumour. A tumour can be
benign or malignant.
Benign tumours are not cancers.
They may grow slowly but do not
spread to other parts of the body.
Malignant tumours are cancerous
growths and have the potential to
spread to other parts of the body.
Breast cancer is a malignant
tumour which occurs when breast
cells become abnormal and divide
without control or order.
The majority of breast cancers start
in the milk ducts. A small number
start in the milk sacs or lobules.
Within these two groups, some grow
very slowly while others develop
Breast cancer can spread to the
lymph nodes and to other parts of
the body such as the bones, liver,
lung and sometimes to the brain.
Ductal carcinoma in situ (DCIS) generally does not cause symptoms, and is most commonly discovered in screening mammograms. Occasionally, women with DCIS may present with a breast lump or bloody nipple discharge.
Breast cancer is otherwise usually painless and there may be no symptoms in the early phase when breast cancer first develops.
When the cancer grows, signs and symptoms may develop and they can include:
The causes of breast cancer are not exactly known but there are risk factors that increase the chance of developing breast cancer. Having risk factors do not mean a woman will definitely develop breast cancer, as many women who have had breast cancer did not have any apparent risk factors.
Some risk factors such as gender and age, or those related to our environment cannot be changed (non-modifiable), while others are modifiable as they are related to our lifestyle choices.
Non-modifiable Risk Factors
Being a woman is a risk factor for developing breast cancer. Women have a much higher chance of developing breast cancer than men due to the female hormones oestrogen and progesterone.
This risk is increased with longer hormonal exposure in women with early menarche (onset of menstruation) before the age of 12 and late menopause (after the age of 55).
Other hormonal-related factors include never having children, late childbearing (after the age of 30), and obesity, especially excessive weight gain in post-menopausal women. This risk also increases with age.
Genetic factors and family history of breast cancer, especially in a first-degree relative (mother, sister or daughter), or two or more close relatives such as cousins and the presence of genetic alterations in certain genes such as BRCA1 and BRCA2 which are associated with significant lifetime risks of breast cancer.
A past history of breast cancer, radiation exposure for medical reasons and certain benign conditions such as atypical ductal hyperplasia, atypical lobular hyperplasia or lobular carcinoma in-situ diagnosed on breast biopsy also increase the risk.
Modifiable Risk Factors
However, most women who have breast cancer have none of the above risk factors. Likewise, not possessing any of these risk factors does not mean that one will not get breast cancer. There is ongoing research to learn more about these factors, as well as ways to prevent breast cancer.
Reducing the Risk of Breast Cancer
There is no sure way to prevent breast cancer, but the risks can be lowered.
These include modifying the risk factors which we have control over such as:
In high-risk women, such as those with a very strong family history or have genetic mutations such as the BRCA, risk-reducing options include taking drugs or having surgery that can reduce their risk. Risk-reducing surgeries include removal of the breast (mastectomy) and removal of the ovaries.
An alternative management strategy to risk-reduction methods is close surveillance. While this does not reduce the risk of cancer development, it does improve outcome by discovering the cancers in earlier stages, allowing earlier treatment and hence better outcomes.
Genetic Risk Assessment for Hereditary Breast Cancer & Implications
What is Hereditary Breast and Ovarian Cancer (HBOC) syndrome?
About 5 to 10 percent of breast cancers can be attributed to hereditary breast and ovarian cancer (HBOC) syndrome. Genetic change (mutation) in the BRCA1 or BRCA2 gene is the most common cause of HBOC.
Individuals with BRCA1 or BRCA2 mutation tend to develop cancer at an earlier age than the general population and have higher risk for bilateral breast cancer, a second primary tumour in a different tissue, and cancer recurrence.
Mutations in other less common genes have also been found to increase the risk of developing breast and other cancers.
Who might be at risk?
HBOC is an adult-onset, cancer predisposition syndrome which can be passed down through generations.
The history of cancer in your close relatives is a clue about the chance of HBOC syndrome in your family. It is more likely if one or more of the following features can be confirmed in your family:
How is HBOC syndrome diagnosed?
Genetic testing for HBOC syndrome is a blood test that is available at the Cancer Genetics Service at NCCS when specific criteria are met. Genetic testing is complex, thus it does not take place without genetic counselling and the process of informed consent.
What does genetic counselling involve?
Cancer genetic counselling is a process to assess a person's risk of having an inherited susceptibility to cancer. It is usually provided by a genetic counsellor and/or cancer geneticist to help people understand and adapt to the medical, psychological and familial implications of genetic contributions to cancer.
Genetic counselling can help you better understand the outcomes and impacts of genetic testing and the possible implications when finding a genetic mutation of HBOC syndrome.
What can I do to reduce my risk of developing breast or ovarian cancer if I have a BRCA gene mutation?
Increased surveillance (clinical breast exam, mammogram and MRI) and consideration of risk-reducing interventions (such as chemoprevention and preventive mastectomy or oophorectomy) are recommended.
What should I do if I am concerned?
If your family history of cancer suggests HBOC syndrome, please talk to your doctor regarding your concerns and they will make the necessary arrangements if a genetic risk assessment is needed.
Finding a genetic mutation of HBOC syndrome may help to:
Breast cancer can be classified by the stage of cancer at diagnosis and their biological characteristics. These will determine treatment recommendations as it has prognostic (most likely outcome of the disease) implications and treatment implications.
Understanding the stage of the cancer is important to understand the prognosis and the treatment recommendation.
Cancers treated in earlier stages have better outcomes, more advanced cancers will need more aggressive treatment.
Cancer stage is based on:
The TNM staging system is based on:
T: Size of the tumour
N: Lymph node involvement
M: Metastasis when cancer has spread to other organs like the lung, liver and bones.
Different T, N and M in combination will determine the stage of the cancer.
Stage 0 or Ductal Carcinoma in Situ (DCIS) is a common non-invasive breast cancer, where cancer cells are still within the ducts and have not grown out to breach the duct linings into the surrounding normal breast tissue.
DCIS, also known as Stage 0 breast cancer, unlike invasive breast cancer, is not life-threatening, but it can increase the risk of developing an invasive breast cancer.
lnvasive breast cancer occurs when cancer cells spread beyond the ducts or lobules resulting in invasive ductal and invasive lobular breast cancer, the two most common subtypes of breast cancer.
Metastatic breast cancer refers to the stage when the cancer has spread beyond the breast to distant organs such as the lungs, liver or bones.
TNM Classifications of Breast Cancer
Breast cancers are also differentiated by the presence of special receptors on the surface of the cancer cells, such as the:
This is associated with the aggressiveness of the cancer and affects the prognosis of the patient.
More importantly, there are drugs to target these changes, and hence directed treatment for them will improve the outcome.
The histopathological (microscopic appearance) subtype of the cancer also helps to determine the prognosis, and nature of breast cancer overall.
The grade (assessment of how abnormal the cancer cells look) also determines the aggressiveness and hence, treatment recommendations.
The most common subtype is the invasive carcinoma of no special type (NST). Specific subtypes include invasive lobular, tubular, cribriform, metaplastic, apocrine, mucinous, papillary and micropapillary carcinoma, as well as carcinoma with medullary and neuroendocrine (WHO classification 2012).
If there is an unusual lump or changes in the breasts, seek medical attention. Try to pinpoint the area accurately as this will assist the doctor with the examination. Tests will be recommended to obtain a definite diagnosis.
Mammography is a low-powered X-ray technique that gives a picture of the internal structure of the breast. Usual screening mammograms involve taking X-ray images of the breast compressed between two plates with two views taken — cranial caudal or horizontal and mediolateral oblique or diagonal.
Additional angles and magnified views may be taken if there are areas of concern. It can detect the presence and position of the abnormalities and help in the diagnosis of breast problems, including cancer.
Any previous mammograms (and reports if available) should be brought along when seeing a doctor.
Sometimes a lump that can be felt is not seen on a mammogram. Other tests may be necessary to determine if the lump is cancerous.
Breast ultrasound is the use of high- frequency sound waves to produce an image of breast tissue.
The sound waves are transmitted from the probe through the gel into the body. The transducer collects the sounds that bounce back and a computer then uses those sound waves to create an image.
c. Magnetic Resonance lmaging (MRI)
This uses a combination of magnetism and radio waves to build up a picture consisting of detailed cross-sections of pictures of the breasts.
The test involves lying on the stomach on a padded platform, with cushioned openings for the breasts, that passes through a tunnel-like structure (which forms a very large magnet). It may take up to one hour to complete, but is completely painless.
MRI is useful when mammograms are not suitable, e.g. in young women with dense breast tissue or when findings on mammograms and ultrasound are not conclusive to achieve a diagnosis.
It is used as a screening tool for young women with high-risk factors like BRCA gene carriers or those with a very strong family history of breast cancer.
This involves taking multiple X-rays of each breast from many angles. The breast is positioned the same way as in a conventional mammogram, but only a little pressure is applied, just enough to keep the breast in a stable position during the procedure.
An X-ray tube moves in an arc around the breast while images are taken. Information is sent to a computer, where it is assembled to produce clear, highly-focussed 3-dimensional images throughout the breast.
a. Fine Needle Aspiration (FNA)
A syringe with a very fine needle is used to withdraw fluid or cells from a breast lump. This is a simple procedure and can be uncomfortable but is usually tolerable enough for it to be done in the clinic.
If the lump is just a cyst, withdrawing fluid in this manner will usually make the cyst disappear.
However, if the lump is solid, your doctor may use this procedure to withdraw some cells from it. The cells will then be sent to a laboratory for examination.
b. Core Needle Biopsy
This is a minimally invasive method that obtains a few tiny strips of tissue from an area of abnormality with a wide bore needle. Local anaesthetic is injected to numb the breast area, followed by a small incision in the skin to allow easy insertion of the needle.
If the abnormality is non-palpable (not detectable by clinical examination) and visible on the ultrasound, ultrasound guidance is used to obtain the tissue. Usually 2 to 6 cores of tissue will be obtained for examination.
A nurse will apply compression to the breast to stop any bleeding. The wound is closed by a steristrip and the dressing applied. Strenuous activity is to be avoided for 2 days after the biopsy.
c. Vacuum-assisted Core Needle
Vacuum-assisted biopsy (VAB) devices use a larger bore needle with a vacuum component to obtain tissue samples from non-palpable lesions.
Like the usual core biopsy, this minimally invasive procedure is also performed under local anaesthesia, which is injected to numb the breast area, followed by a small incision in the skin to allow easy insertion of the needle. It is used for lesions seen by mammography (stereotactic-guided biopsy), ultrasound or MRI.
The surgeon or radiologist places the probe into the suspicious area of the breast accurately. A vacuum then draws the tissue into the probe, a cutting device removes the tissue sample and then carries it through the probe into a collection area.
More tissue is usually obtained using the VAB than the usual core needle biopsy and the number of strips removed is dependent on the area that needs to be examined.
A small titanium clip (microclip) may be placed at the biopsy site as a location marker for future treatment. This clip is very small (2 mm), is harmless, and will not cause any problems when left inside the breast. An X-ray is taken post-biopsy to ensure proper clip placement. New biodegradable markers are also available now.
A nurse will apply compression to the breast to stop any bleeding, the wound is closed by a steristrip and the dressing applied. Strenuous activity is to be avoided for 2 days after the biopsy.
This procedure is minimally invasive as compared to an open surgical biopsy. It is performed as a day surgery procedure. lt has the ability to sample tiny abnormalities called microcalcifications, making early diagnosis of breast cancer possible.
Under local anaesthesia, it takes about 30 to 45 minutes to complete. The procedure is usually not painful but you may experience some discomfort.
d. Excision Biopsy
An excision biopsy is the removal of a lump or sample of suspicious tissue by surgery for examination under a microscope to give a definite diagnosis.
For lesions that are small or not palpable, accurate marking of the area for surgery is necessary. These include using ultrasound during surgery, or with procedures done just before surgery to mark the area to be operated.
Ultrasound, mammogram or MRI can be used to insert a small thin wire to the abnormal spot in the breast.
This wire is used to guide the surgeon to remove the area accurately. This technique is known as Hook Wire Localisation (HWL) Biopsy.
An alternative method known as Radioisotope Occult Lesion Localisation (ROLL) uses a small amount of radioactive substance injected into the lesion. This area is detected with a radioactive sensor used during surgery that allows the lesion to be accurately removed.
This technique does not have the discomfort of the hookwire and the need to perform mammograms after the wire placement to check their positions.
Excision biopsies are often performed under general anaesthesia, depending on the size and position of the lump, but local anaesthesia may be used for small lesions close to the skin.
As a minor day surgery procedure, patients can return home after surgery. Strenuous activity is to be avoided for the first few days; immediate ability for usual light activities of daily living is expected.
Post-operative advice may differ between individuals depending on their needs and circumstances. In general, most will be able to return to work in a week.
Treatment of breast cancer often involves more than one therapy, and may be a combination of therapies.
Treatment recommendations depend on factors such as the cancer type, stage of the cancer, size of the tumour in relation to the breast size, whether breast preservation is desired and the patient’s general health.
Personal preferences de-termine certain choices, if the option is available, such as the options for the type of surgery. Being diagnosed with breast cancer and having to decide on the treatment options may be difficult. The support of friends and family during the consult and discussion on the results of tests and treatment is recommended.
Local and Systemic Therapy
Chemotherapy, hormone therapy, and targeted therapy are systemic therapies.
In early breast cancer, surgery is the first treatment of choice. Chemotherapy, targeted and hormonal therapy may be used before surgery (neoadjuvant therapy), or after surgery (adjuvant therapy). Radiotherapy is usually given after surgery.
In stage IV cancer, the goal is to stabilise the disease with systemic therapy. However, local treatment of tumours with radiation therapy or surgery may be recommended when symptoms need to be alleviated.
SurgerySurgery for breast cancer is considered in two parts: breast and axillary lymph nodes.
I. Breast SurgeryThe two broad options are breast- conserving surgery (BCS) or mastectomy.
1. Breast-Conserving Surgery (BCS)
Wide Excision Breast-Conserving Surgery
In this surgery, the breast cancer and a rim of normal surrounding breast tissue are removed. The breast will remain; a scar and some changes in shape and size of the breast are expected. Patients can go home on the same day or the next day.
After recovering from breast-conserving surgery, radiation therapy to the breast (Mon to Fri) for 3 to 6 weeks is recommended. It helps to reduce the risk of recurrence.
A second operation is needed if cancer cells are noted at the edge in the histological (microscopic) assessment of the removed portion. This occurs in 10 to 15 percent of patients.
Oncoplastic Breast-Conserving Surgery In some patients undergoing breastconserving surgery, additional procedures may be recommended to prevent severe deformities of the breast.
Image-Guided Localisation for SurgeryFor non-palpable tumours that need to be removed with surgery, localisation with a hookwire or a localising substance under image guidance done prior to the surgery is needed.
This procedure is performed under local anaesthesia, prior to surgery. Mammogram, ultrasound or MRI guidance is used to accurately locate the site for surgery.
A fine wire (hookwire) is inserted or a radioactive substance is injected into the breast, within or in close proximity to the lesion of interest, which will be removed during the surgery.
Mastectomy is the removal of the whole breast (incorporating the breast tumour). In general, there are two types of mastectomy:
The drain will be removed when the drainage is less than 30 ml a day after 1 to 2 weeks. Drain and wound care will be taught to patients and their caregivers before discharge and patients can go home the next day.
Types of Post-Mastectomy Reconstructions
i. Flap reconstructions
Skin, fat and sometimes muscle (a flap) from another part of your body may be used to make into a breast shape. This operation takes about 6 to 8 hours and requires a hospital stay of between 1 to 2 weeks. Several drains are used and removed after 1 to 2 weeks. Flaps may be from the following areas:
Additional procedures to improve the look of the breast after the initial surgery may include adding a nipple, surgery to the opposite breast to create a good match, or refining the shape of the recreated breast.
ii. Breast implants
Silicone implants may be used to create a new breast and the operation takes about 4 to 5 hours. There are usually 2 to 3 drains inserted and the hospital stay is 2 to 5 days.
1-stage procedure is when the permanent implant is inserted at the time of mastectomy. A
2-stage procedure is when a temporary expander is placed at the time of mastectomy and gradually expanded to stretch the skin. The expander will be exchanged for a permanent implant at a later surgery.
II. Axillary Surgery
If the dye or radioactive substance is not able to identify the SLN, removal of all the lymph nodes (axillary clearance) will be done.
A separate axillary incision is often needed for patients undergoing breast conserving surgery.
Complications from Surgery As with all surgical procedures, complications can occur. Risks of general anaesthesia include allergy to anaesthetic agents, heart attack, stroke and deep vein thrombosis, especially for longer surgeries.
Our anaesthetists will assess all patients before surgery to ensure they are optimised and prepared for surgery to minimise these risks.
Surgical complications include:
After surgery is planned, referral to the Breast Care Nurse (BCN) Service is necessary. Our Breast Specialist Nurse will explain and explore concerns and issues pertaining to breast cancer and the treatment options, and plan pre-operative, operative and post-operative management to ensure successful treatment and recovery.
Consult time for individual patients vary from 30 to 75 minutes. A personal contact number will be provided for convenience and the BCN will be a resource person for patients and their families in the coordination of the various appointments before and after surgery in the treatment journey.
Post-operative services include wound and drain care, rehabilitation, education programmes and prosthesis-fitting.
High-energy rays are used to kill cancer cells or stop them from growing further.
Although radiation therapy can affect both cancer cells as well as normal cells, the aim of radiation is to destroy more cancer cells and spare as many normal cells as possible. Radiation therapy is given to the affected breast after a lumpectomy.
In some circumstances, it may be given to the chest wall after a mastectomy, or to the lymph nodes. It is usually given 5 days a week on weekdays, over a period of 3 to 6 weeks.
Radiation therapy can cause some side effects which vary among individuals.
The degree and intensity of the skin reaction is greater in patients receiving a large standard dose and in patients who have fair skin. Skin texture also becomes darker and thicker.
The breast may swell, and increase or decrease in insensitivity. Usually, these effects are temporary and are manageable.
This treatment uses anti-cancer drugs to prevent cancer cells from growing and reproducing themselves. These drugs are usually given by injection through veins into the blood stream to all parts of the body.
It is usually given over 3 to 6 months and may be used alone, before surgery (neoadjuvant) or after surgery (adjuvant) therapy, or together with targeted therapy to increase the effectiveness of the treatment, depending on the type and stage of cancer.
Chemotherapy is given in cycles. Each cycle consists of a treatment period followed by a resting (recovery) period. As cancer drugs also affect normal cells, the resting period is to allow the body to recover before the next treatment cycle starts.
2. Targeted Therapy
Breast cancers are also tested for special receptors. One such receptor is the Human Epidermal Growth Factor 2 (HER2) receptor. This receptor is over-expressed in about 25 percent of all breast cancers; the presence needs to be confirmed by laboratory tests performed on the biopsy specimen before the treatment is given.
The aim of the treatment is to reduce and hopefully eliminate existing cancer cells in the human body while minimising side effects on normal cells.
Trastuzumab, also known as Herceptin®, targets the HER2 (Human Epidermal Growth Factor 2) receptors on cancer cells to prevent cell growth and division.
Herceptin® has been shown to prolong survival in breast cancer patients with early and advanced disease (Stage IV) when used in combination with chemotherapy.
An increasing number of targeted drugs are becoming available for the treatment of breast cancer, including Lapatinib (which targets HER2 and EGFR) and Bevacizumab (which targets a factor associated with new blood vessel formation in tumours.
3. Hormonal Therapy
Breast cancers are tested for oestrogen receptors (ER) and progesterone receptors (PR) on their surfaces as such cancers can be stimulated by oestrogen or progesterone to grow.
Hormonal therapy is aimed at blocking this effect. The drug recommended is dependent on the menopausal status of the women.
Hormonal therapy can cause some side effects, and they are dependent on the type of drug taken and can vary from one patient to another.
Any unusual bleeding should be reported to the doctor. It is recommended for pre-menopausal women, but can be used in postmenopausal women.
Side Effects: Serious side effects from Tamoxifen are rare but Tamoxifen can cause the formation of blood clots in the veins, especially in the legs. In a very small number of women, Tamoxifen can cause cancer in the lining of the uterus. You may be referred to a gynaecologist to evaluate any unusual bleeding.
Any unusual bleeding should be reported to the doctor. It is recommended for pre-menopausal women, but can be used in postmenopausal women.
You may be referred to a gynaecologist to evaluate any unusual bleeding.
Regular follow up by the doctor after treatment is recommended due to the risk of developing breast cancer again.
This will include physical examination of the chest, underarms, neck, and the other breast with periodic mammograms.
Changes to look out for include:
Wound and Drain Care
Wounds are often closed with absorbable stitches, hence stitch removal is not needed.
Wound care is simple and patients will be taught and given specific instructions in the management of various types of wound coverage.
Patients are recommended to shower 2 days after most surgeries such as breast-conserving surgery and simple mastectomies.
Soft flexible tube drains are placed under the skin at the time of surgery. These help to remove blood and other fluids that accumulate at the site of surgery. Patients without breast reconstruction surgery are usually discharged from the hospital with the tube drain on the day after surgery.
The nurse in the ward will teach the drain care and provide a chart to keep a record of the drainage, to be reported to the Breast Care Nurse (BCN) daily. The drain will be removed in the clinic when the drainage is minimal and this usually takes 1 to 2 weeks.
Patients are recommended to see a doctor if there is:
Medication and Diet
Routine medications prescribed by doctors are usually resumed immediately after surgery and there are diet restrictions unless otherwise advised by the doctor.
Activity and Rehabilitation
Patients are encouraged to resume normal mobility and function as soon as it is suitable after surgery.
Most patients with breast-conserving surgery (BCS) and simple mastectomies will be able to resume usual daily activities immediately after surgery, with special precautions for those with breast reconstruction surgery, where management will differ according to their surgeries.
Arm Exercise Programme
Our Arm Exercise Programme conducted by our Occupational Therapists or Physiotherapists on the day after surgery aims to prevent shoulder and arm stiffness. This will enable you to use the arm as you had before surgery in activities at home, work and in recreation.
The exercises also promote circulation of the lymphatic system, thus preventing swelling of the affected arm. Over-strenuous activities are to be avoided in the first few weeks after discharge.
These exercises are to be done once daily, and each set of exercises is to be repeated 5 times. Instructions from the Occupational Therapist or Breast Care Nurse on the limitations will be advised as needed.
Arm and Hand Care
Following axillary surgery, lymphoedema and increased risk of infection of the arm may occur as lymph nodes also contain cells which fight infection.
Therefore, extra care to protect the hand and arm on the operated side from injury is recommended.
Patients will be referred to a physiotherapist or occupational therapist specially-trained in treating lymphoedema. They will recommend programmes which include skin care, exercise, manual lymphatic drainage (a special massage technique), and compression garments to help reduce the swelling.
Arm care measures include:
Self-arm massage may be recommended to encourage lymph drainage and minimise risk of arm lymphoedema. The following is a simple technique. The massage should be light and gentle without causing redness during and after the massage.
With a mastectomy, physical appear-ance can be maintained by wearing a prosthesis (called a breast form), or by undergoing breast reconstruction.
There are women who choose not to have breast reconstruction after mastectomy. Some make this decision because they want to avoid extra surgery. For others, it is because they are comfortable with their appearance and body image.
Breast forms or prostheses are used to maintain appearance and a sense of balance, as well as to relieve the strain on posture that may occur after a mastectomy. They are available in a variety of sizes, shapes and colours. Some are designed to fit into a special bra. Others can be attached securely to your chest using a special adhesive.
The information provided on this page does not replace information from your healthcare professional. Please consult your healthcare professional for more information.
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