Cancer care in Singapore
The Cancer Institute at National University Hospital, Singapore
Singapore is a small country, but it is ideally and
centrally located to conveniently serve not only its population but also
patients from the surrounding regions. It�s economy is sufficiently strong to
maintain highly sophisticated and expensive equipment to manage a high level of
healthcare, including oncology services.
Cancer incidences in Singapore are on an upward trend
based on the report of the Singapore Cancer Registry for the period of
2001-2005. Cancer is the number one cause of death in Singapore. The three most common cancers for males in Singapore, in decreasing occurrences,
are colorectal, lung, and prostate. For females, the three most common cancers
are breast, colorectal, lung cancers. Technological advances and advances in
anti-cancer drugs have transformed cancer management leading to improved
outcomes worldwide and in Singapore as well. The epidemiology and management of
these common cancers in Singapore are presented. While Singapore presently has five radiotherapy centres (3 public, 2 private) to service its
population of 4.5 million and regional needs, the government has plans to
expand its radiotherapy services to accommodate the aging population and the
rising expectations of increasingly affluent cancer patients seeking advanced
cancer care. The current and future initiatives spearheaded by Singapore to achieve excellence in this aspect are discussed. � 2008 Biomedical
Imaging and Intervention Journal. All rights reserved.
Keywords: Cancer care, Singapore
Cancer, being the most common cause of death in Singapore, accounts for 30% of all deaths annually. Epidemiological data is continuously
being collected at the Singapore Cancer Registry, and data is obtained via
notifications by the physicians, pathology records, hospital records and death
certificates . Table 1 shows the number of incident cancers by year of
diagnosis from 2001 to 2005. In general, there was an upward trend in the
number of incident cancers by year of diagnosis. Table 2 shows the number of
incident cancer by gender in the same time period. Crude incidence rates for
total male and female cancer patients in the same time period were 235.7 and
248.5 per 100,000 Singapore resident population respectively.
Tables 3 and 4 show the top ten most frequent cancers in
males and females for the period 2001-2005. Although colorectal and breast
carcinoma were the most common carcinomas respectively in males and females,
lung, colorectal and liver cancers were the top 3 causes of cancer mortality in
males, while breast, lung and colorectal cancers were the top 3 causes of
cancer mortality in females.
In comparison with Western countries, Singapore has higher incidence rates for cancers of the nose, stomach and liver, and lower
rates for cancers of pancreas, skin and prostate. The high incidence of
colorectal cancers, which is approaching that of the West for both males and
females, is due to an increasingly affluent society, with lifestyle habits such
as smoking and diets rich in meat and fat being major contributing factors.
Prostate cancer is the 3rd most common cancer
in Singaporean males from 2001-2005, and is the number six cause of mortality
amongst Singaporean males. The incidence of prostate cancer in Singaporean
males is increasing, in part due to the widespread use of PSA (prostate
specific antigen) as a screening test. PSA screening is commonly included in
many health screening programmes.
Breast cancer is the leading cause of death in Singaporean
women. Singapore has one of the highest age-adjusted breast cancer incidences
in Asia with increasing incidence in women in their 50�s. Mammographic
screening in Singaporean women increases the rate of detection of early breast
cancers, with acceptable recall, needle biopsy rates.
Among the ethnic groups, colorectal, lung and prostate
cancers were the three most common cancers among the three ethnic groups. Age
standardised rates were highest among Chinese males, followed by Malay and
For females, breast and colorectal cancers were the most
common and second most common cancers respectively. The age standardised rates
were highest among Chinese females, followed by Malay and Indian females. Lung
cancer was the third most common among Chinese females, fourth among Malay
females and eighth among Indian females.
Current management of the top 3 cancers in males and females
The 3 top cancers among males and females are lung,
colorectal and breast cancer (in females). Management entails surgery,
radiotherapy or chemotherapy, either alone or in combination.
Upon suspicion of lung cancer, definitive biopsy is
obtained by the diagnostic radiologist or respiratory physician via
- Fine needle aspiration and cytology
- Brochoscopy and biopsy
The patient is staged with a CT scan of the
brain/thorax/abdomen and bone scan while a PET CT can be performed as an
additional staging procedure, especially prior to surgery, to aid treatment
decisions for selected patients. Tumour stage is ascribed following the 2002
AJCC staging guidelines . Management is different for non-small cell lung
cancer (NSCLC) and small cell lung cancer (SCLC).
For patients with NSCLC, surgery offers the patient
with resectable disease the best chance of a cure. Surgical approaches include
wedge resection, lobectomy or pneumonectomy. The type and extent of surgery
performed depends on the patient�s functional status and extent of disease.
Chemotherapy is given concurrently with
radiotherapy for patients with locally advanced disease. The agents used
include cisplatin and vinblastine.
In the adjuvant setting, chemotherapy is given for
patients with Stage Ib-III disease post-resection. The agents used include
cisplatin, vinorelbine, carboplatin and paclitaxel.
Radiotherapy is an alternative for patients who are
not suitable for surgery or for patients who decline surgery. Definitive
radiotherapy is given for patients suitable for curative treatment, but decline
surgery or chemotherapy. The dose and fractionation regimen depends on
patient�s performance status / choice and treatment volume. Options include 60-70
Gy in 30-35 fractions given over 6 to 7 weeks, or 50 Gy in 20 fractions given
over 4 weeks. Radiotherapy is delivered via 3-Dimensional Conformal
Patients with stage IIIA disease are treated with Surgery
and/or chemoradiotherapy depending on performance status and patients with
stage IIIB disease are treated with chemoradiotherapy.
For patients who are not suitable for curative treatment
or for patients with metastatic disease, palliative radiotherapy/chemotherapy
or best supportive care are acceptable options. The aim is palliation of
symptoms and/or prolongation of life.
Radiotherapy techniques such as Intensity Modulated
Radiotherapy (IMRT) are available in Singapore and can be used in selected
cases of lung cancer unsuitable for surgery. Local control is important in
NSCLC since at least 30-40% of patients die from local or locoregional
progression of disease. For curative treatment, doses in the range of 60-70 Gy
are required. IMRT allows for the improvement in therapeutic ratio. A recent
review from the Memorial Sloan Kettering Cancer Centre showed that IMRT
resulted in promising outcomes for inoperable patients with NSCLC .
Currently IMRT is not the standard of care for lung cancer
in Singapore, until technology for respiratory gating is available and
optimised for clinical application. A carefully implemented respiratory gated
IMRT programme is essential for the accurate and safe delivery of higher than
conventional radiotherapy doses.
Patients with limited stage SCLC are managed with a
combination of chemotherapy and radiotherapy.
Chemotherapy agents used include cisplatin and etoposide.
Radiotherapy is given concurrently with chemotherapy, most often commencing
with the 1st or 2nd cycle of chemotherapy. The dose of
radiation used is in the order of 50-54Gy, given daily over a period of 5-6
weeks. Radiotherapy is delivered via 3DCRT. Prophylactic cranial irradiation is
recommended for suitable patients with complete and good partial response after
Patients with extensive stage SCLC are managed with
The diagnosis of colorectal cancer is done by colonoscopy
and biopsy. Patients are staged with a CT scan of the thorax/abdomen/pelvis. A CT scan of the brain and bone scan is done if brain and bone metastasis is suspected.
The definitive treatment for colorectal cancer is surgery.
While surgery alone is curative for early stage colorectal cancer, adjuvant
chemotherapy and/or radiotherapy is employed in patients with locally advanced
disease to reduce the risk of local recurrence and improve survival.
Surgical approaches for colon cancer includes
- Polypectomy and local excisions, which is performed for superficial
cancers or polyps.
- Colectomy (hemicolectomy/segmental resection), which involves removing
part of the colon as well as regional lymph nodes.
- Laparoscopy-assisted colectomy, which involves removal of part of the
colon as well as regional lymph nodes.
Surgical approaches for rectal cancer includes
- Polypectomy and local excisions, which is performed for superficial
cancers or polyps
- Low anterior resection, where the tumour is removed with the regional
lymph nodes with preservation of anal sphincter function
- Abdominal perineal resection, whereby the surgeon makes 2 incisions, one
in the abdomen, another in the perineum. The tumour/regional lymph nodes are
removed together with the anus and sphincter muscle. Because the anus is
removed, a permanent colostomy is required.
- Pelvic exenteration is uncommonly performed for locally extensive rectal
cancers. A colostomy is required and a urostomy (opening on the abdominal wall
for urine to flow into a bag) is required if the bladder is also removed.
Adjuvant chemotherapy is given for patients with stage III
colon cancer and also for patients with stage II colon cancer with high risk
features (T4 disease, perforation of tumour, poorly differentiated tumour,
positive margin). Agents used include 5 Flurouracil/leucovorin with platinum
based compounds such as oxaliplatin. Other targeted agents such as cetuximab
are increasingly being employed.
For colorectal cancer, adjuvant chemoradiotherapy is given
for patients with stage T3-4 or node positive rectal cancer. The chemotherapy
regimen used is 5 Flurouracil/leucovorin for 5 cycles with radiotherapy given
concurrently with the 3rd cycle of chemotherapy.
The dose of adjuvant radiotherapy prescribed is 45 Gy in
25 fractions over 5 weeks duration to the whole pelvis, followed by a 5.4 Gy in
3 fractions to boost the tumour bed. This dose is increased to 9 Gy in 5
fractions if there is a positive margin.
Preoperative chemoradiation can also be given for locally
advanced rectal tumours, to attempt to down-stage the tumour. The neoadjuvant
approach has been shown to lead to an increase in local control, decrease acute
toxicity and increase sphincter sparing rates.
Adjuvant radiotherapy is not routinely given for colonic
tumours or descending colon/sigmoid colon tumours above the peritoneal
reflection because of inability to deliver radiotherapy accurately and safely
to an organ that can move freely. Radiotherapy is delivered via 3DCRT.
Breast cancer is detected using mammography, or by the
patient either as a palpable lump, or changes in the breast (including nipple
discharge, overlying skin changes). Mammographic screening enables early
detection and intervention of breast cancers, resulting in a reduction in
breast cancer mortality. Breast cancer is most commonly diagnosed by a fine
needle aspiration and cytology. Other approaches include trucut biopsy or
Early breast cancer can be cured with mastectomy
alone. With the advent of sentinel lymph node biopsy, a full axillary
dissection can be avoided, hence avoiding the attendant complications of
infection, seroma, bleeding and lymphedema.
An alternative to mastectomy is breast conservation.
Breast conservation therapy entails wide local excision with axillary surgery
followed by adjuvant radiotherapy to the affected breast.
The dose of adjuvant radiotherapy is 50Gy in 25 fractions
to the whole breast followed by a 10Gy in 5 fraction boost to the tumour bed. A
large number of randomised trials have demonstrated equivalence in long term
survival compared with mastectomy with this approach.
The use of adjuvant radiotherapy following breast surgery
has been shown to improve the survival of patients in clinical studies and
Adjuvant radiotherapy is given using 3DCRT technique. For
patients with large pendulous breast, IMRT can be used to reduce hot spots and
to ensure a homogenous dose distribution, hence reducing acute and late side
Adjuvant hormonal therapy is prescribed if the patient has
hormone receptive breast cancer. In premenopausal patients, tamoxifen
(selective estrogen receptor antagonist) is used while in postmenopausal
patients, tamoxifen or an aromatase inhibitor (including Anastrozole,
Letrozole, Exemestane) can be used as an alternative. The aromatase inhibitors
have been shown to have less side effects such as hot flushes, endometrial
cancer, vaginal bleeding, cardiovascular accidents, and thromboembolic events
compared to tamoxifen. However, they are associated with an increase in
arthralgia and fractures, and hence should not be used for patients with
Other options of hormonal treatments include ovarian
ablation with surgery or radiotherapy and ovarian function suppression with
luteinising hormone-releasing hormone agonists such as goserelin.
Adjuvant chemotherapy is recommended for patients with a
combination of adverse risk factors including younger patients, lymph node
positivity, grade of tumour, lymphovascular invasion, Her2neu receptor
positivity and tumour size.
Commonly used chemotherapy agents include anthracyclines
such as doxorubicin in combination with cyclophosphamide and 5 Fluorouracil.
Taxanes such as paclitaxel and docetaxel are used in patients with node
positive disease, or in patients with high risk node negative disease.
Locally advanced breast cancer is treated with a
combined modality approach. Mastectomy with an axillary dissection is performed
if the tumour is surgically resectable. This is followed by adjuvant
chemotherapy and adjuvant radiotherapy respectively. Adjuvant hormonal
treatment is recommended for patients with hormone responsive disease.
Surgically unresectable tumours are treated with
neoadjuvant chemotherapy followed by mastectomy. Adjuvant radiotherapy +/-
hormonal therapy is given thereafter.
If the tumour is still unresectable after neoadjuvant
chemotherapy, then radiotherapy is given first before surgery is attempted.
In patients who are unfit or decline chemotherapy,
neoadjuvant hormonal therapy is an alternative to neoadjuvant chemotherapy in
The dose of radiotherapy given in the adjuvant setting
post mastectomy is 50Gy in 25# to the chest wall over 5 weeks duration. The
supraclavicular fossa and/or axilla are included in the treatment fields when
Present and Future
Since its independence in 1965, Singapore has quickly
grown from being a developing country to a developed country with a population
in excess of 4 million. Cancer incidence has increased and so has demands for
comprehensive cancer care.
Singapore has a well-established radiotherapy service
catering to the local as well as regional cancer patients. There are currently
five radiotherapy centres in Singapore, two private centres and three centres
based in government hospitals (which provide for both government subsidised and
private cancer patients). For the public centers, the National Cancer Centre
based at the Singapore General Hospital currently has 9 linear accelerators,
one with Novarlis stereotactic radiosurgery/radiotherapy capabilities and one
brachytherapy suite. The Cancer institute at National University Hospital and at Tan Tock Seng is equipped with 4 linear accelerators in total and one
brachytherapy suite. In the private sector, the Gleneagles radiation oncology
unit is equipped with two linear accelerators, and Mt Elizabeth Hospital with
one linear accelerator and one state-of-the-art tomotherapy machine. Both
private and public centres have established surgical and medical oncology
centers to provide comprehensive cancer services.
The majority of local patients are treated at public
centres. The waiting time for radiotherapy varies from a few days to as long as
six weeks depending on center and urgency of treatment. In view of the aging
population and the rising expectations of increasingly affluent cancer patients
seeking advanced care, there are plans for growth of the cancer services in
both public and private sectors. For example, a second national cancer centre
with enhanced radiotherapy facilities is being built at the Kent Ridge National University Hospital campus in addition to the development of at least 2-3
new private radiotherapy centres. All of the proposed expansion plans are timed
to occur in the next 4-5 years. However the expansion will also require a
significant increase in staff, which will not be able to be completely covered
locally. Thus recruitment for trained, experienced staff will also have to be
conducted regionally. In conjunction with the increased services there will
also be more emphasis placed on academic development and research particularly
in the newly planned National University Cancer Institute Singapore (NCIS), as
Table 1 Number of incident cancers by year of diagnosis, 2001-2005.
Table 2 Incidence of cancer by gender, 2001-2005
Table 3 Ten most frequent cancers in males, 2001-2005
Table 4 Ten most frequent cancers in females, 2001-2005
Singapore Cancer Registry Interim Report. Trends in Cancer incidence in Singapore 2001-2005.
AJCC cancer staging manual. 6th edition. 2002.
Sura S, Gupta V, Yorke E et al. Intensity-modulated radiation therapy (IMRT) for inoperable non-small cell lung cancer: the Memorial Sloan-Kettering Cancer Center (MSKCC) experience. Radiother Oncol 2008; 87(1):17-23.
|Received 13 August 2008; accepted 14 August 2008
Correspondence: Radiation Oncology Department, The Cancer Institute at National University Hospital, Singapore. E-mail: firstname.lastname@example.org (Khai-Mun Lee).
Please cite as: Tey J, Baggarley S, Lee KM,
Cancer care in Singapore, Biomed Imaging Interv J 2008; 4(3):e38