What is Breast Cancer
Breasts are made up of fat and gland tissue. All glandular tissue in the breast
is made up of individual cells that reproduce under the control of hormones.
Sometimes this process goes out of control and an abnormal cell develops.
This is the beginning of cancer.
Cancers of the breast usually start in the cells of the milk ducts.
How common is Breast Cancer
Breast cancer remains the most common female cancer in Singapore since
population-based registration started in 1968. Up to 20% of all cancers
diagnosed in women are breast cancers. During 1998-2002, an annual
average of 1100 women was diagnosed with breast cancer and an annual
average of 273 women died from the disease. The peak incidence of breast
cancer in women in Singapore is from 55-59 years.
However, nine out of 10 women who go to their doctors with breast lumps
have a benign disorder, not cancer. Normal changes associated with the
menstrual cycle can make breasts feel lumpy.
While the aetiology of breast cancer is multifactorial, most women with breast
cancer have no high risk factors and may differ between individual women
and racial groups. It is clear that breast cancer has a genetic basis upon
which internal hormonal influences, diet and external environmental factors
Age and gender
The risk of breast cancer increases with age. Most women who are
diagnosed with breast cancer are more than 45 years old.
Prolonged fertile period, i.e. the first menstrual period at a young age
and the late onset of menopause. A woman who has menopause at 55
years has twice the risk of a woman who has menopause at 45 years.
Women who have never been pregnant also have a high risk of breast
cancer. Getting pregnant for the first time after the age of 30 also
increases the risk. On the other hand, breast-feeding protects against
Hormone replacement therapy after menopause may increase the risk
but is effective against many other diseases. These issues should be
discussed with a gynaecologist before embarking on hormone
Use of oral contraceptive pills. Birth control pills may slightly increase
the risk for breast cancer, depending on age, length of use, and other
factors. No one knows how long the effects of the pill last after stopping
Family history and genetic factors
Between 5 to 10% of all breast cancers are associated with genetic
factors. The genes BRCA1 and BRCA2 have been identified and may
be associated with breast cancer. But not everyone with the abnormal
gene will develop breast cancer. Testing for these genes is not widely
available as yet.
Some studies show previous breast, uterine, ovarian, or colon cancer,
and a strong history of cancer in the family may increase the risk for
breast cancer. Such history may indicate genetic factors.
Obesity is controversial as a risk factor. Some studies report obesity as a
risk of breast cancer, possibly associated with higher levels of estrogen
production in obese women.
Diet high in saturated fat and alcohol.
Significant alcohol use (more than 1-2 drinks a day) has been associated
with an increased risk of breast cancer.
Types and Stages of Breast Cancer
There are several different types of breast cancer.
Ductal carcinoma begins in the cells lining the ducts that bring milk to
the nipple and accounts for more tha n 75% of breast cancers.
Lobular carcinoma begins in the milk-secreting glands of the breast
but is otherwise fairly similar in its behavior to ductal carcinoma. Other
varieties of breast cancer can arise from the skin, fat, connective
tissues, and other cells present in the breast.
Classification based on
Size of the primary tumour.
Receptor status (type of hormone receptors in breast cancer
cells): Breast cancer cells are classified as estrogen receptor
positive and negative and progesterone receptor positive or
The estrogen receptor is a protein in breast cancer cells that
binds to estrogen. About half of all breast cancer patients have
this protein and are called estrogen receptor positive (ER+).
Patients lacking this protein are classified as estrogen receptor
Nodal status - the presence or absence of cancer cells in glands
or lymph nodes; if so, how many and which nodes.
Metastasis - the spread of cancer into other tissues.
STAGE 0 BREAST CANCER
In Situ ("in place") disease in which the cancerous cells are in their
original location within normal breast tissue. Known as either DCIS
(ductoral carcinoma in situ) or LCIS (lobular carcinoma in situ)
depending on the type of cells involved and the location, this is a pre-
cancerous condition, and only a small percentage of DCIS tumors
pregress to become invasive cancers.
There is some controversy within the medical community on how to
best treat DCIS. Options include remova l of the tumour (lumpectomy)
and the breast and surrounding tissues are irradiated (radiation
therapy) or the entire breast (mastectomy).
STAGE 1 BREAST CANCER
Tumours are 2 cm or less in size
No lymph node involvement
Usually the lump is surgically removed (lumpectomy) and the breast
and surrounding tissues are irradiated (radiation therapy). The radiation
destroys any remaining tumour cells.
Additional chemotherapy or hormonal therapy may be considered
depending on the clinical situation.
STAGE 2 BREAST CANCER
Tumours are more than 2 cm but no more than 5 cm in size.
Lymph nodes may be involved (which means tumour has traveled from
the tumour located in the breast via the lymphatic system to lymph
nodes lying along the course of lymphatic vessels located in the
The tumor (lumpectomy) or the entire breast (mastectomy) as well as
any affected lymph nodes are surgically removed.
Radiation therapy will be used if a lumpectomy was performed.
Chemotherapy will usually be given to destroy any cancer cells that
have spread beyond the breast.
Hormone therapy may be used, usually for postmenopausal women
who have ER-positive tumors.
STAGE 3 BREAST CANCER
Tumours are more than 5 cm with lymph node involvement.
Removal of the entire breast (mastectomy) and the affected lymph
Chemotherapy may be used prior to surgery to reduce the size of the
tumour, or after surgery to eliminate any cancer cells remaining in the
breast or other regions of the body.
Hormonal therapy may be used after surgery to eliminate any cancer
cells remaining in the breast or other regions of the body for ER-
STAGE 4 BREAST CANCER
Advanced cancer in which the cancer cells have spread (metastasized)
to other parts of the body, most often the lungs, brain, bones, or liver.
The goal is to stabilize the disease.
Tumour is surgically removed where possible, especially in cases
where symptoms must be alleviated.
Systemic therapy (treatment that goes throughout the entire body) may
Hormone therapy is used for ER-positive tumours and sometimes used
for ER-negative tumours, although the patient's menopausal status and
how progressive the cancer is will also affect this treatment decision.
Tumour may be treated with chemotherapy and / or radiation therapy.
The clinical stage of breast cancer is the best indicator for prognosis
(probable outcome), in addition to some other factors. Five-year survival rates
for individuals with breast cancer who receive appropriate treatment are
95% for stage 0
88% for stage I
66% for stage II
36% for stage III
7% for stage IV
Symptoms and Signs of Breast Cancer
About 80% of women with breast cancer first consult their doctor with a
symptom they notice themselves. The most common is a breast lump.
Sometimes the nipple may be increasingly puckered or there is change in the
appearance of the skin on the breast, s uch as redness or the appearance of
pits, like orange peel. There may also be a discharge from the nipple.
Lymph glands of the armpit may also be enlarged and appear as lumps.
In advanced stages, breast cancer can spread to the liver, lung, bone and
brain. Abnormalities in these organs may also be present.
Any worrisome breast changes should be confirmed and investigated by a
After getting as much information as possible about the symptom and any risk
factors, the physician performs a physical examination including both breasts,
armpits, and the area of the neck and chest.
(See investigations for Breast lumps)
Ultrasound scan of the breasts
- Fine needle aspiration cytology (FNAC)
- Core needle biospy
- Open surgical Biopsy
Metastatic and Treatment Workup
If breast cancer is diagnosed, additional testing is performed, including chest
X-ray and blood tests. Surgery, radiation, chemotherapy, or a combination of
these may then be recommended, not only for treatment, but also to help
determine the stage of disease and whether the cancer has spread. Staging is
important to help guide future treatment and follow-up, and to give some idea
of what to expect in the future.
Chest X-ray: to look for spread to the lungs
Bone scan: to look for spread to the bone
Ultrasound of the liver: to look for spread to the liver
Computed Tomography (CT): sometimes used to verify or confirm the
findings from the chest X -ray or ultrasound scan of the liver.
Heart Scan: may be performed if chemotherapy is recommended
Management of patients with breast cancer may involve surgery,
radiotherapy, systemic chemotherapy, hormonal therapy or a combination of
these. The availability of a breast care nurse and a multidisciplinary team is
helpful in guiding a patient through the required treatments.
Surgery is almost always required to treat breast cancer.
1. Local (Breast) Surgery
The aim is to conserve the breast if possible. This is do ne by wide
excision, i.e. the removal of the cancer with an appropriate amount of
surrounding tissue. When this is not possible either due to a large tumour
or presence of multiple tumours in the breast, total removal of the affected
breast, i.e. mastectomy, is required.
2. Regional (Axillary) Surgery
Lymph glands under the armpit (axilla) are usually removed, i.e. axillary
clearance at the same time for Stage 1 and above. This can be
undertaken as sentinel lymph node sampling (for small breast tumours) or
a standard axillary lymph node dissection.
3. Breast reconstruction
Breast reconstruction after mastectomy is also possible with collaboration
with the plastic surgeons and this can be done either at the time of surgery
or as a delayed procedure. Options include the use of implants and the
patient’s own tissue flaps. Techniques including skin sparing mastectomy
have improved the aesthetic results.
Pain may occur after surgery for the first few days but this can be
controlled by medication. It is also common for patients to feel tired or
weak for a while. The length of time it takes to recover varies from patient
Complications of surgery include hematoma or seroma formation
beneath the skin flaps, wound infection, flap necrosis, nerve injury,
shoulder stiffness, pain and upper limb lymphoedema.
Aim: Cancer cells left in the remaining breast tissue may cause the cancer
to recur in the breast at a later date, i.e. local recurrence, therefore,
radiotherapy may be necessary after surgery. In radiotherapy, high-energy
rays are used to kill cancer cells and stop them from growing and dividing.
Like surgery, radiotherapy is a local treatment; it can affect cancer cells
only in the treated area. Radiotherapy is usually given on an outpatient
basis, 5 days a week, for 5 to 6 weeks. Patients are not radioactive during
or after treatment.
Radiotherapy is almost always mandatory if only a wide excision of the
cancer is performed.
Patients with mastectomy may also be recommended chest wall
radiotherapy if they have spread to the armpit (>4 nodes) as this is
associated with increased risk of recurrence
Aim: Treatment with medicines to kill cancer cells is called chemotherapy.
Chemotherapy aims to eradicate the occult distant spread, to prevent
cancer recurrence in other parts of the body such as the lung, liver and
other tissues. It is usually recommended for younger women where the
breast lump was larger than 2cm at time of diagnosis or if the cancer also
involved the lymph glands in the armpits.
Most of these medications are injected into a vein or a muscle. The
medicine flow through the bloodstream to nearly every part of the body,
damaging cells that are rapidly dividing and growing. Normal cells that are
rapidly dividing and growing, such as white blood cells, will also be
affected by chemotherapy. Because cancer cells are often more immature
and fragile than normal cells, chemotherapy affects cancer cells more than
they do normal healthy cells.
Type: The exact choice of drugs will depend on the person's general
health and other medical illnesses, and the stage of the cancer.
Chemotherapy is generally given in cycles over 4 to 6 months: a treatment
period is normally followed by a rest period, then another treatment period,
and so on. Most chemotherapy can be given on an outpatient basis.
Current first line regime is an anthracycline-based regimen for about 4
months id the patient is fit for it.
Side effects are usually mild nausea or vomiting, hair loss, lethargy or
tiredness, and loss of appetite. Most women will be able to carry on
working during this period. Radiation therapy may also cause a temporary
lowering of the white blood cell count, cells that help protect the body
against infection. The side effects are usually temporary, developing
gradually over the weeks of the treatment, and improving gradually after
treatment is completed. Medication will usually be prescribed to minimise
these side effects.
Neoadjuvant chemotherapy: If the breast cancer was especially large,
more than 5 cm at time of diagnosis, chemotherapy is given to shrink the
tumour before surgery is performed.
In certain medical centres, high dose chemotherapy and bone marrow
transplantation or peripheral stem cell rescue is offered as an experimental
option after surgery to try to prolong survival in women considered to have
an extremely high risk of cancer recurrence.
Since breast cancer is hormone dependent, hormone treatment may have
an effect on certain types of breast cancer. So in older women and women
who have reached menopause, tamoxifen may be prescribed for 5 years.
This is used to block the effects of estrogen that may otherwise help
breast cancer cells to survive and grow. Most women with breast cancers,
which express estrogen or progesterone on their surface benefits from
treatment with tamoxifen.
Its side effects are well tolerated including hot flushes, weight gain and
vaginal dryness. However, it is associated with a small increased risk of
venous thrombotic disease, endometrial hyperplasia and cancer.
A new class of medicines called aromatase inhibitors, such as Aromasin,
has been shown to be as good or possibly even better than tamoxifen in
women with stage IV breast cancer.
Biological therapy, also called immunotherapy, is an entirely new type of
anti-cancer drug. It uses the body's own immune system to fight infection
and disease or protect the body from some of the side effects of other
forms of treatment. It can be used alone or with chemotherapy.
Trastuzumab (Herceptin) is an example of this class of drugs. It affects
how cancer cells function and grow. Some 20 - 25% of breast cancers
respond to trastuzumab. Trastuzumab is not chemotherapy, but it may be
combined with chemotherapy. Recent studies show that adding
trastuzumab to chemotherapy or treating with trastuzumab after
chemotherapy helps prevent the cancer from coming back and can make
people who had HER2-positive breast cancer live longer.
Monoclonal antibodies, interferon, interleukin-2, and colony-stimulating
factors such as GM-CSF and G-CSF, are forms of biological therapy.
These treatments often cause temporary flu-like symptoms such as fever
and chills, muscle aches and weakness, loss of appetite and diarrhoea.
Breast Care Service
Assessment of post operative patients
Provide follow up care
A 2-view examination is usually done. Further evaluation with cone
magnification may be indicated for suspicious lesions.
It is recommended that women aged 40 - 49 should go for mammography screening
once a year, and women above 50 should go for one once in 2 years.
Mammography is currently the most reliable way to detect breast cancer in
asymptomatic patients. It can detect lumps even before they are felt by the hand.
Such early detection can greatly increase chances of recovery as well as provide
more treatment options.
BREAST CARE SERVICE
Breast cancer can be a devastating experience for patients. They require
psycho-social support and encouragement to cope with the disease and
subsequently surgery. The breast care nurse clinician plays an
important role as a counsellor to help patients and their families cope
with the physical and emotional difficulties arising from the treatment.
She also runs the Breast Clinic where patients come for follow -up
review and teaches them exercise that will help them regain their
mobility. A firm advocate of breast screening and breast self-
examination for early cancer detection, she actively promotes this
awareness among patients and the nursing staff by giving talks and
providing informational materials.
Scope of service
Breast care education
Breast cancer support
A. Scope of Service
1. Pre-operative counselling.
2. Assessment of post operative patients
3. Provide follow up care
4. Provide other support