Issue No. 12 • MICA (P) 149/10/2009
AN NCCS BI-MONTHLY PUBLICATION September / October 2010
...HELPING R E A DERS TO ACHIEV E GOOD HE A LTH Salubris is a Latin word which means healthy, in good condition (body) and wholesome.
Higher concentration of SN-38 in blood causes neutropenia
CPT-11
Higher concentration of SN-38 in intestines causes severe diarrhoea
CE
SN-38
SN-38
UGT1A1 UGT1A9
ENTERIC BACTERIA
SN-38G
SN-38G
RESPONDING DIFFERENTLY TO IRINOTECAN
UNDERSTANDING WHY EACH OF US RESPONDS DIFFERENTLY TO DIFFERENT DRUGS
PAGE A2
In Other Words
SALUBRIS
September / October 2010
The genetic make-up of individuals has increasingly become the reason for more in-depth research into why human beings respond to drugs differently. VERONICA LEE speaks with A/PROF BALRAM CHOWBAY on his research on Irinotecan, which led to a change in its labeling by the Ministry of Health.
I
rinotecan has long intrigued A/Prof Balram Chowbay, Principal Pharmacologist, from the Laboratory of Clinical Pharmacology at NCCS, so much so that he now uses it as a model drug to learn more about the interactions between pharmacogenetics and pharmacokinetics of pharmacological agents. Prof Chowbay joined SGH in 1990 and moved over to NCCS in 1999. The quest into the varying responses had come during his early days in the ICU, when he had often wondered why patients responded differently to therapeutic agents when they are given a standard dose of drug. During that time, there was not much information about the role genes played in influencing drug action and how genomic factors caused variations in drug metabolism and response.
PHARMACOLOGY OF IRINOTECAN IV CPT-11
SYSTEMIC CIRCULATION LIVER
CPT-11
CES
SN-38
CYP3A4
SN-38
UGT1A1 UGT1A9
NEUTROPENIA
SN-38G
ENTEROHEPATIC CIRCULATION
CESs NPC CYP3A4/5 APC
CPT-11 SN-38
EFFLUX TRANSPORTERS ABCB1 ABCC1 ABCC2 ABCG2
SN-38
SN-38G
-GLUCURONIDASE
SN-38G
SN-38
SN-38G CPT-11
SN-38
COLON
SMALL INTESTINE
SN-38
DIARRHOEA
With the knowledge that drugs are metabolized by specific enzymes that are encoded by specific genes, he began studying the variability present in genes that were responsible for encoding drug metabolizing enzymes and drug transporters involved in regulating the pharmacokinetics of drugs to assess the therapeutic outcomes for patients. Thus began an arduous journey into translational research. In a recent research, Prof Chowbay has found that Uridine Diphosphate Glucuronosyl Transferase 1A1 (UGT1A1), a type of gene in the liver, can affect the way Irinotecan, a drug that is used to treat colon cancer, is metabolized to its active metabolite, SN-38 in the liver. The UGT1A1 gene exists in two different forms, the normal (so-called wild-type form) and the homozygous variant form. Two different defective alleles, UGT1A1*6 and UGT1A1*28 are responsible for the low enzymatic activity of the encoded UGT1A1 protein in humans. Patients carrying two copies of the homozygous variant form of UGT1A1*6 or UGT1A1*28 allele have low amounts of the UGT1A1 enzyme in the liver and are unable to detoxify the SN-38 effectively. This leads to severe toxicity such as low white blood cells which compromises the defense mechanism in the body and severe diarrhea.
PAGE A3
In Other Words
SALUBRIS
September / October 2010
Following studies done in the US and Japan, which suggested that Irinotecan toxicity is linked to variants of UGT1A1, such as UGT1A1*6 and UGT1A1*28, Prof Chowbay examined the situation in local contexts. It was found that the frequency of UGT1A1*6 was similar in all the Chinese, Malays and Indians at approximately 1%. However, the frequency of UGT1A1*28 was approximately 13% in Indians compared with 2% to 4% in Chinese and Malays. Similar to studies done abroad, the genotype distribution of UGT1A1*28 polymorphism in Indians are similar to Caucasians, while the Chinese have similar distribution as the Japanese.
The study pointed to the fact that patients carrying this defective genetic constitution in the UGT1A1 gene can have higher levels of the cytotoxic metabolite of Irinotecan, SN-38 which is approximately 100 to 1,000-fold more active than Irinotecan and may be more susceptible to irinotecan induced serious toxicity. It also highlighted that ethnic differences to irinotecan induced toxicity exist in the Asian population. It has also helped doctors to better identify patients who will most likely tolerate Irinotecan vis-à-vis those who can’t when they send their patients’ blood samples for genetic test before receiving the drug.
Explaining why he chose to embark on such a study, Prof Chowbay elaborated, “There is wide individual variability in the pharmacokinetics, pharmacodynamics, and tolerance to anticancer agents within a particular ethnic group and ever greater variability among different ethnic groups. Understanding the contribution of genetic factors to drug action has the potential to provide personalized therapy based on an individual’s genetic makeup and hence maximize efficacy and reduce adverse events. Thus it makes sense to study the inherent variability present in genes responsible for encoding the different proteins involved in regulating the actions of drugs.” Although the study has made some headway in clinical care of patients, Prof Chowbay revealed that the study had been a challenging one. To begin with, it was difficult to examine the influence of UGT1A1 polymorphisms on the pharmacokinetics of Irinotecan in the different ethnic groups in Singapore as the majority of patients belong to the Chinese ethnic group. Another challenge was working with the Health Sciences Authority and the Pharmacogenetics Advisory Committee to recommend a suitable package insert update for the drug based on his findings. This was effected early this year in Singapore. Despite the challenges, Prof Chowbay is able to envisage the light at the end of the tunnel. He sees the potential in continuing such studies. “Singapore, with its multi-ethnic population, can be regarded as a mini-global research hub. Studying the impact of pharmacogenetic factors on the pharmacokinetics of drugs in such a multi-racial society is fantastic. This is exactly what the industry is interested in and I think we should capitalize on this advantage that we already have,” he said.
“Singapore, with its multiethnic population, can be regarded as a miniglobal research hub. Studying the impact of pharmacogenetic factors on the pharmacokinetics of drugs in such a multi-racial society is fantastic. This is exactly what the industry is interested in and I think we should capitalize on this advantage that we already have.” A/Prof Balram Chowbay Continued on page A4
UNDERSTANDING WHY EACH OF US RESPONDS DIFFERENTLY TO DIFFERENT DRUGS
PAGE A4
In Other Words
SALUBRIS
September / October 2010
Continued from page A3.
While it can be said that Prof Chowbay has made progress in his field and feels he has arrived to an extent, the straight-talking man thinks that there is a lot more to be done. “Healthcare cost is high and finding ways to select the right patients for the right drug will certainly help to reduce the financial burden on patients as well as decrease morbidity and mortality. Furthermore, this translational approach to treatment is becoming more important with the newly available molecularly targeted agents. The latter are drugs designed to hit certain deregulated pathways in cancer cells and they are very costly. Identifying patients who would benefit most from these new drugs is of paramount importance. This would depend on the identification of specific biomarkers that can tell us the nature of the activated or deregulated pathway in a patient’s tumor. Such information can aid in the selection of patients who would respond optimally to a selected targeted agent. We are still working on that.”
IRINOTECAN GENOTYPE-DIRECTED DOSING IN ASIAN CANCER PATIENTS
UNIFORM PATIENT POPULATION
UGT1A1 *28/*28 + UGT1A1 *6/*6
UGT1A1 *1/*1 UGT1A1 *1/*28 UGT1A1 *1/*6
As an extension of his achievements, Prof Chowbay is now investigating how genetic polymorphism in genes affects clinical outcomes for breast cancer patients who are on tamoxifen therapy. While tamoxifen is a cheap and effective drug, its active metabolite, endoxifen, which is mediated by the CYP2D6 enzyme, is highly polymorphic. Interim studies have found that approximately 50% of the Chinese population carries the deficient CYP2D6*10 form which decreases CYP2D6 enzymatic activity. Such patients may produce limited amounts of endoxifen (the active metabolite of tamoxifen) and hence may derive limited therapeutic benefit from tamoxifen. “The goal is to identify patients who may not derive optimal benefit from tamoxifen and channel them to other treatment modalities,” he said.
UGT1A1 *1/*1 UGT1A1 *28/*28 UGT1A1 *1/*6
UGT1A1 *1/*1 UGT1A1 *6/*6 UGT1A1 *1/*28
Aside from this and other on-going Phase 1 and 2 studies involving combinations of anticancer agents based on their mechanism of actions and pharmacokinetics among the ethnic groups in Singapore, of paramount importance to Prof Chowbay is the continual research on suitable biomarkers that will be useful in designing scientifically sound and early phase proof-of-concept type of clinical trials and treatment modalities.
TRIM YOUR CANCER RISK WITH EXERCISE!
Exercise is one of the most important actions you can take to help guard against many types of cancer. Up to one-third of cancer-related deaths are due to obesity and a sedentary lifestyle which are among the main causes of two of the most common cancers in Singapore such as breast and colon cancers.
M
any people exercise to prevent heart disease, but exercise can also play a key role in preventing cancer. Most cancers are caused by lifestyle factors—not genes. As an example, women living in developing countries have a much lower risk of breast cancer. One reason may be because they tend to be more physically active than women in industrialized countries.
REDUCE YOUR WAISTLINE & YOUR BREAST CANCER RISK Many studies have shown that women who exercise have a 30 to 40 percent lower risk of breast cancer than their sedentary peers. The female hormone estrogen seems to play a key role. Women with high estrogen levels in their blood have increased risk of getting breast cancer. Since exercise lowers blood estrogen, a woman’s breast-cancer risk is thus reduced. Older women need to be concerned about estrogen, because after menopause the hormone is produced by fat cells. Women who exercise have less fat and therefore produce less estrogen. With more than 1300 new breast-cancer cases diagnosed in Singapore each year where all the three major ethnic groups are equally affected, preventing cancer through exercise is one of the best ways a woman can take charge of her health.
WIN THE BATTLE AGAINST COLON CANCER Exercise plays a dramatic role in preventing cancer of the colon and rectum. Many studies show that people who exercise reduce their risk of colon cancer by 20 percent or more compared to people who do not exercise, and the benefits are seen in both men and women, although the effect is greater in men.
PAGE B1
Looking Forward
SALUBRIS
September / October 2010
GET OFF THE COUCH! It is easier than you think! A half hour of physical activity daily such as walking, swimming or leisurely bike riding will get you started. Here are some other ways to be more active: • Use stairs rather than the elevator. • Walk or bike to your destination, and walk around the block after dinner.
Changes in digestive acids and other substances also occur with exercise, and these changes are believed to provide some protection from colon cancer. Decreases in body fat, insulin and other growth factors also may contribute to lower colon-cancer risk.
• Exercise at lunch and take a light snack afterwards to replenish lost energy.
HOW MUCH EXERCISE IS ENOUGH?
• Vary your type of exercise so you will not get bored or think it is a chore.
An ongoing National Institute of HealthAmerican Association of Retired Person’s Diet and Health study revealed that men and women who do regular vigorous physical activity had a 10 to 20 percent lower risk of developing cancers of the colon, rectum, lung, and kidney. Also, women who were physically active after menopause had a lower risk of breast cancer than women who were not physically active. Singapore’s Health Promotion Board recommends 30 minutes of moderate intensity (heart rate: 60 to 80 percent) aerobic activity a day, 5 days a week or 20 minutes of vigorous intensity (heart rate: 80 to 85 percent) aerobic activity a day, 3 days a week. You can also combine both moderate and vigorous activity to meet the recommendations. 30 minutes of aerobic activity can be accumulated in bouts of 10 minutes and be incorporated into your daily routine e.g. walking to the nearest bus-stop or MRT station. As you get fitter, you can then do more, increasing the duration and intensity of the physical activity to enjoy better health. To get the most benefit, though, aim for about an hour a day. Moderately intense activities such as brisk walking may be sufficient, but there is more benefit with increased intensity.
• Walk to visit co-workers rather than send an e-mail in the office • Park a little farther from your office, the store or the library for a nice walk.
• Use a stationary bike or do sit-ups, leg lifts and push-ups while watching TV. Often people view exercise narrowly as just a method to lose weight or to look better. These incentives are attractive, but exercise is really about a person taking charge of his or her health, preventing chronic diseases like cancer, and living longer.
IT IS NEVER TOO LATE TO START! Even moderate activity can be critically important in helping menopausal women reduce their risk of cancer, heart disease and other chronic ailments. Exercise reduces fat deep in the abdomen (“intraabdominal” fat), a hidden risk factor because it can raise insulin levels, thus promoting the growth of cancer cells as well as cholesterol levels. Most men and women gain 1 to 2 pounds on average every year, and that adds up to dangerous levels over a lifetime. The beauty of exercise as a method to reduce total and intra-abdominal fat—and therefore chronic disease—is that it can be done by most people at low cost and with low risk of side effects. It is never too late to enjoy the health benefits of exercise!
By Flora Yong
Senior Nurse Manager NCCS
PAGE B2
Looking Forward
SALUBRIS
September / October 2010
CANCER SCREENING – Give Yourself the Edge
Cancer screening is among the most important health prevention methods. The goal of cancer screening is to lower the number of people who develop and die from cancer. Screening is an excellent way to detect cancer early, when it is most easily treated and often cured. Talk to your doctor about the right screening tests for you and their benefits and risks. Below are cancer screening tests recommended for men and women in Singapore.
COLORECTAL CANCER: THE PREVENTABLE DISEASE
According to the Singapore Cancer Registry’s interim report on trends in cancer incidence in Singapore, during the period 2003 – 2007, colorectal cancer was the most common cancer affecting Singaporeans. Although it is more commonly found in people aged 50 years and above, it can also affect adults of any age.
Screening is a perfect way to detect colorectal cancer because the cancer is slow growing. The cancer usually begins with small growths called polyps, which can take 10 or more years to change into cancer. That is why the standard interval for screening the colon is 10 years. Removing polyps in their early, precancerous state ensures they would not be present to cause cancer later. Screening also can identify cancer early, when it can be completely cured. Screening may reduce the risk of being diagnosed with colorectal cancer by as much as 70%. Some people, such as those with family history of the disease, have a higher risk than the general population and would likely benefit from earlier and more frequent screening.
Recommended Screening Frequency for 50 year olds and above:
SCREENING TESTS
WHEN
Faecal Occult Blood Test (FOBT)
Yearly
Sigmoidoscopy
Every 5 years
Colonoscopy
Every 10 years
Barium Enema X-ray
Every 5 – 10 years
BREAST CANCER: SCREENING IS KEY Breast cancer is the most common cancer among Singapore women. A woman’s risk of getting breast cancer increases with age. 70% of all breast cancers are diagnosed in women 40 years of age and older. However, women as young as in their early twenties have been diagnosed with breast cancer in Singapore. Breast cancer can also affect males but the risk is very low compared to females. Currently the best tool for breast-cancer screening is a Mammogram (an x-ray of the breast) together with a Clinical Exam by a doctor. Cancers found on mammograms are usually smaller than cancers that can be felt, and they are less likely to have spread. Regularly scheduled mammograms can increase a woman’s chance of detecting breast cancer early, thus increasing the chances of cure. Women in their 40s and older should have mammograms every one to two years. Women at a higher-thanaverage risk for breast cancer due to one of the following risk factors may need more frequent mammograms or medical evaluations: • If you have had breast cancer before. • If your mother, sister, daughter or two or more close relatives, such as cousins, have had breast cancer. • If you have a breast condition that may predispose you to breast cancer. • If you carry a specific genetic change that increases susceptibility to breast cancer such as BRCA1 (Breast Cancer gene 1) and BRCA2 (Breast Cancer gene 2).
PAGE B3
Tender Care
SALUBRIS
September / October 2010
Recommended Breast Cancer Screening Frequency for Women:
AGE
TESTS
WHEN
Women ≥ 20 years
• Breast Self-Examination (BSE)
Every month
Women 20 to 39 years
• Clinical Breast Exam (CBE) by a healthcare professional
Every 3 years
Women 40 years and above
• Clinical Breast Exam (CBE) by a healthcare professional • Mammogram
Every year
• Clinical Breast Exam (CBE) by a healthcare professional • Mammogram
Every year
High risk women: Start 5 to 10 years before earliest age at breast cancer diagnosis or ovarian cancer in a relative.
Every year
Every year
CERVICAL CANCER: A SCREENING SUCCESS STORY Cervical cancer is the most common cancer of the woman’s reproductive system. The accessibility of the cervix allows the wide use of the Papanicolaou (Pap) Smear as a reliable and economical screening test for cancer of the cervix. All sexually active females should go for regular Pap Smear screening. Cervical cancer is ranked 6th among the top 10 cancers affecting women in Singapore. The good news is, it is largely preventable and that precancerous cervical lesions can be easily diagnosed and removed. Cervical cancer can be cured if detected early. Thanks to effective Pap test screening and treatment, deaths from cervical cancer have declined dramatically over the years. Experts agree that one of the most important things women can do to reduce their risk of cervical cancer is to receive regular Pap tests. Recommended Cervical Cancer Screening Frequency for Women:
AGE
TESTS
WHEN
Women (no later than 21 years old) who have had vaginal intercourse should begin cervical cancer screening about 3 years after their first sexual encounter.
• Pelvic Examination and PAP Smear
Every year
Women age 30 and above who have had 3 consecutive normal Pap tests
• Pelvic Examination and PAP Smear
Every 2 to 3 years
High risk women with multiple partners
• Pelvic Examination and PAP Smear
Every year
Women 70 years or older who have had 3 or more consecutive normal Pap tests
• May choose to stop having Pap tests
Women past menopause still need to have regular Pap tests. However, women who have undergone a hysterectomy in which the cervix was removed do not require Pap testing, unless the hysterectomy was performed because of cervical cancer or its precursors.
PROSTATE CANCER SCREENING: RECOMMENDATIONS MAY VARY Prostate cancer is the 3rd most common cancer among men in Singapore. (Singapore Cancer Registry, Interim Report, 2001-2005). It was ranked 6th in 2002. The number of prostate cancer cases has climbed steadily over the last few years. A majority of prostate cancer cases occur in men 55 or older. Compared to many other cancers, prostate cancer grows very slowly. It may be decades from the time the first cell changes is detected under a microscope until the cancer is big enough to cause symptoms. Recommendations for prostate-cancer screening vary because it is not always clear what benefits would outweigh the risks of some diagnostic tests and treatment. Some doctors encourage yearly screening for men over 50 years old; others recommend against screening; still others counsel men about their risks and benefits on an individual basis and encourage patients to make personal decisions about screening. Men who have a father or brother with prostate cancer have a greater chance of developing the disease, and African-American men have the highest rate of prostate cancer. Therefore, these groups would benefit the most from screening.
The main screening tools are: Digital-rectal exam (DRE) - the doctor feels the prostate gland through the rectal wall to check for bumps or abnormal areas. Patients may experience slight discomfort during the exam. Prostate-specific antigen (PSA) test, measures the level of protein in the blood that rises when the prostate gland enlarges. PSA levels alone do not give doctors enough information to distinguish between benign and cancerous conditions, but doctors take results from this test into account in deciding whether to check for further signs of prostate cancer.
By Flora Yong
Senior Nurse Manager NCCS
PAGE B4
Tender Care
SALUBRIS
September / October 2010
HOW TO TAKE YOUR MEDICINE SAFELY
All of us can play an active and important role in the safe use of medication.
BEFORE TAKING YOUR MEDICINE, MAKE SURE: •
It is the correct medicine
•
It is not expired
•
You are not allergic to the medicine
•
You have read the label carefully
•
You understand the instructions
•
You take the right dose at the right time
BEING KNOWLEDGEABLE ABOUT YOUR MEDICATION CAN HELP TO PREVENT ADVERSE EVENTS FROM MEDICATION ERRORS. YOU CAN PLAY A PART BY: 1
Keeping a current list of any food and medication allergies.
2
Maintaining an up-to-date list of all the medications you take, including vitamins, over-the counter products and herbal remedies.
3
4
5
6
Informing your doctor when you start or stop taking a medication.
7
Keeping your medication in their original containers unless when you are using a pillbox.
Reading and following the directions on prescription labels exactly.
8
Contacting your doctor or pharmacist if you have any questions about your prescription or if you experience any problems with your medication.
9
Discarding any expired medication.
10
Refilling your prescription at the same pharmacy so that pharmacy staff can review your record for potential allergies or medication interactions.
Asking your doctor if a new prescription replaces any of your current medication.
Making a mark on your calendar when you need prescription refills.
OTHER IMPORTANT POINTS: •
Find out if there is any food, medicine or activity to avoid while taking your prescribed medicine
•
Find out what are the possible side effects after taking your prescribed medicine
•
Find out what to do if you forget a dose
•
Never share medicine
•
Take note of the appropriate storage conditions for your medicine
•
Do not accumulate unwanted medicine
Source: NCCS’ Pharmacy Drug Information Leaflet
动一动，减低患癌风险
PAGE B5
往前看 SALUBRIS
September / October 2010
运动是对抗许多癌症的 其中一项重要预防。在与 癌症有关的死亡病例当 中，就有多达三分之一是 由肥胖问题和久坐生活 方式所导致。这包括本地 最常见的两种癌症—乳 癌和结肠癌。
战胜结肠癌
别赖在沙发上！
运动能大大降低结肠癌和直肠癌 的患病风险。许多研究调查显示， 经常运动者患上结肠癌的风险比 一般不常运动的人少了20%。男性 和女性都能享有运动所带来的益 处，但运动对男性的益处较大。
这比想象中容易！您可从每天半小时的 运动，如步行、游泳或骑脚踏车开始。您 可通过以下方式使生活更活跃： • 别搭电梯，改爬楼梯。 • 步行或骑脚踏车到目的地、晚饭后在 组屋区里散步。 • 利用午餐时间运动，过后吃些点心补 充精力。 • 别发电邮，走到的同事座位讨论公事。 • 把车停放在距离办公室、商店或图书 馆较远处，然后步行到目的地。 • 从事多种不同的运动，避免感到厌倦。 • 边看电视节目，边踩运动脚踏车或 做仰卧起坐、抬腿以及伏地挺身等 运动。
运动也会导致消化酸和其他物质 产生变化，而这些变化相信能预 防结肠癌。减少体内脂肪、胰岛 素以及其他生长因素也能降低运 动者患上结肠癌的风险。
多少才足够？ 许多人为了预防心脏疾病而运动，但运动也 能在预防癌症中扮演重要的角色。多数癌症 的导因和生活作息有关，而并非基因。举例 说明，现今发展中国家的妇女患上乳癌的风 险较低。原因之一或许是她们的体力活动一 般比工业化国家女性的来得高。
减少腰围尺寸，减低乳癌风险 许多研究调查显示，经常运动的妇女患上乳 癌的风险与不活跃的同僚相比，少了30%至 40%。雌激素似乎扮演着举足轻重的角色。 血液中含有高雌激素的妇女患上乳癌的风 险较高。由于运动能使血液中的雌激素下 降，这将能降低妇女患上乳癌的风险。运动 也能减少导致癌细胞增长的其他因素，如胰 岛素。 较年长的妇女也该关注雌激素含量，因为更 年期后，雌激素是由脂肪细胞所产生的。经 常运动的女性体内有较少脂肪，也产生较少 雌激素。新加坡每年诊断出超过1300多起 乳癌病例（本地三大族群—华族、马来族和 印族的妇女均受影响），而通过运动预防癌 症是女性掌控自己的健康的最有效的方法 之一。
全国健康学院－美国退休人士饮 食及健康协会正在进行的一项研 究调查显示，经常进行激烈运动 的男女患上结肠癌、直肠癌、肺 癌以及肾癌的风险减低了10%至 20%。此外，更年期过后的妇女若 体力活动活跃，患上乳癌的风险 也会降低。 新加坡保健促进局建议人们进 行一周五天，每次30分钟的中 等烈度有氧运动（心跳：60%至 80%），或一周三天，每次20分 钟的激烈有氧运动（心跳：80% 至85%）。您也可以综合不同 烈度的运动，以达到所需的要 求。30分钟的有氧运动可错开 为三个10分钟，融入您的日常作 息，例如步行到邻近的巴士车站 或地铁站。当您的健康进步后， 您能增加运动的时间和激烈程 度，并享有更好的体魄。每天运 动一小时将能达到最佳效果。虽 然如竞走等中等烈度的运动一 般算是足够，但越激烈的运动将 能带来更大的益处。
人们往往视运动为减肥或使外形更亮眼 的途径。运动除了能带来这些益处，更能 让人掌控自己的健康，预防癌症等慢性 疾病，让人更长寿。
马上行动！ 即便是中等烈度的运动也能显著帮助更 年期妇女减低患上癌症、心脏疾病和其 他慢性疾病的风险。男性和女性的体重 每年平均增加一至两磅，日积月累，积少 成多。腹部的深层脂肪会提高胰岛素水 平，促进癌细胞的生长以及提高胆固醇 水平，而运动就能降低这个隐藏风险。 运动能减少体内的总脂肪和腹部的深 层脂肪，并减低患上慢性疾病的风险。 运动的美妙之处也在于它无需太大的花 费，而且副作用的风险低。马上行动，享 受运动带来的好处吧！
作者: 杨宝燕 高级护士经理 新加坡国立癌症中心
癌症筛查—有备无患
PAGE B6
往前看 SALUBRIS
September / October 2010
癌症筛查是预防性医疗服务中其中一项 重要的服务。癌症筛查的目的在于减少患 癌身亡的人数。筛查是及早检测癌症的 最佳方法，越早检测，治愈的几率越高。 您可以和您的医生讨论哪些筛查适合您， 以及个别筛查的益处和风险。以下是我们 建议新加坡男女进行的癌症筛查。
结肠直肠癌－可预防的疾病 新加坡癌症注册局针对本地的癌症病发率的中期报告 显示，从2003至2007年，结肠直肠癌是本地最普遍的 癌症。尽管患癌病人年龄通常在50岁以上，但任何年龄 的成人都有可能患上结肠直肠癌。 由于结肠直肠癌是生长比较缓慢的癌症，因此筛查的 成功率很高。它通常由胃肠道息肉开始，这些息肉有可 能在10年左右以后变成癌细胞。因此，结肠镜检查的 间隔期为10年。在息肉未变成癌细胞前将它切除，意 味着它不会引发癌症。趁早筛查能及早检测癌症，并完 全治愈。 筛查能将您患上结肠直肠癌的风险减低70%。家中有 家庭成员患上结肠直肠癌者，患癌风险比一般人高，因 此及早和更频密的筛查将带来益处。 50岁以上者的建议筛查频率 筛查检测
频率
粪便隐血检验
每年
乙状结肠镜检查
每五年
结肠镜检查
每十年
钡灌肠X光
每五至十年
乳癌－筛查是关键 乳癌是新加坡女性患上的最普遍的癌症。女性患上乳癌 的风险随着年龄的增长而提高。70%被检测出的乳癌患 者年龄为40岁或以上。然而，本地也有20多岁的女性患 上乳癌。男性也可能患上乳癌，但和女性相比，男性病患 的风险非常低。 目前，最有效的乳癌筛查是乳房X光检验，以及医生的 临床检测。乳房X光检验探测出的癌细胞往往比能触摸 到的癌细胞来得小，而这时候癌细胞也应该还未扩散。 定期进行乳房X光检验能提高妇女及早检测出患癌的几 率，同时提高治愈的可能性。 40岁或以上的女性应该每一至两年进行乳房X光检验。 属于较高风险群的女性也应该更频密进行乳房X光检验 或医生的临床检查。高风险群女性包括： • 曾经患上乳癌者 • 母亲、姐妹、女儿或表姐妹患上乳癌者 • 出现易患乳癌的乳房症状者 • 体内含有特定的基因变化，如乳腺癌基因1(BRCA1) 以及乳腺癌基因2(BRCA2)者，也较有可能患上乳癌
女性乳癌筛查的建议频率 年龄
检验
频率
20岁以上的女性
• 乳房自检
每个月
20至39岁的女性
• 专业医护人员的临床乳房检验
每三年
40岁或以上的女性
• 专业医护人员的临床乳房检验 • 乳房X光检验
每年 每年
高风险群女性： 一旦亲人患上乳癌或卵巢癌，应比一 般人提早5至10年开始各项检查
• 专业医护人员的临床乳房检验 • 乳房X光检验
每年 每年
子宫颈癌－筛查检验成功性高 子宫颈癌是妇女生殖器官最普遍的癌症。颈宫的位置使子宫颈抹片为最经济、可靠的筛查方式。所 有性活跃的女性都应该定期进行子宫颈抹片筛查。 在本地，子宫颈癌在女性患上的十大癌症中排行第六。但好消息是，子宫颈癌预防性高，而且癌前期 宫颈病变容易诊断及切除。若及早诊断，子宫颈癌能治愈。多亏有效的子宫颈抹片筛查和治疗，子宫 颈癌所夺走的性命逐年来显著下降。专家认同，女性预防子宫颈癌的重要步骤之一就是定期接受子 宫颈抹片检验。 女性子宫颈癌的建议筛查频率 年龄
检验
频率
21岁以下的女性在首次发生性行为的 约三年后就该开始子宫颈癌筛查
• 盆腔检查以及子宫颈抹片
每年
30岁以上、连续三次进行普通子宫颈 抹片检验的女性
• 盆腔检查以及子宫颈抹片
每两至三年
拥有多名性伴侣的高风险女性
• 盆腔检查以及子宫颈抹片
每年
70岁以上、连续超过三次进行普通子 宫颈抹片检验的女性
• 可选择停止子宫颈抹片检验
更年期过后的妇女仍得定期进行子宫颈抹片检验。然而，曾进行子宫切除手术的女性则无需进行子 宫颈抹片检验，除非进行子宫切除手术是因为子宫颈癌或其前兆。 前列腺癌－筛查建议不一 前列腺癌是本地男性第三普遍患上的癌症（新加坡癌症注册局中期报告，2001至2005年）。它于 2002年排行第六。过去几年，前列腺癌的病例逐年增加。患上前列腺癌的男性多数为55岁或以上。 和其他癌症相比，前列腺癌的生长速度缓慢。从第一个癌细胞在显微镜下的改变，直到癌症病发， 整个过程可长达几十年。前列腺癌的筛查之所以可能建议不一，是因为有些筛查和治疗须冒一定的 风险，却不一定能带来相等的益处。有些医生建议50岁以上的男性每年进行检验；有些医生则不建 议筛查；还有医生根据每名病人的情况，告知筛查检验的风险和益处，然后由病人自行决定是否接 受筛查。 父亲或兄弟患上前列腺癌的男性有更高的患病几率，而非洲裔美国男性患上前列腺癌的几率最高。 因此，这些高风险群将能从筛查中得到最多的益处。 主要筛查检验为： 直肠指检—医生透过直肠前壁触摸前列腺是否有肿块或非寻常之处。病人在检验中可能会稍微感 觉不舒服。 前列腺特异性抗原检验—在前列腺扩张时检测血液内的胆固醇含量。这项检验并不能给予医生足 够的资料分辨良性或癌症状况，但医生能凭检验结果决定是否进一步检测前列腺癌的症状。
作者: 杨宝燕 高级护士经理 新加坡国立癌症中心
如何安全服用药物
PAGE B7
温柔呵护 SALUBRIS
September / October 2010
人人都能在药物的安 全使用中扮演重要的 角色。
服药前，务必确保： • 那是正确的药物 • 药物尚未过期 • 您对药物不会产生过敏 • 您已详细阅读药物标签 • 您了解服药指示 • 您在指定的时候服用正确的剂量
对您的药物多加了解能避免因错误服用药物而导致的不 良后果。您可：
其他注意事项： • 询问服药时是否得避免服食
1
维持一份食物及药物过敏
6
清单。 2
维持并定时更新您所服用的
7
所有药物，包括维他命以及柜
一旦开始或停止服用药
任何食物及药物，或避免从事
物，务必通知医生。
任何活动。
除非使用药丸盒，否则将 药物放置在原来的盒子。
台购买的药物和草药。 8 3
详读并遵照药物标签的指示。
• 询问服用该药物可能导致的 副作用。 • 询问若忘记服用药物该怎
在日历上作记号，提醒自
么办。
己填补药物。 • 千万别和他人共用药物。
4
若对药剂有任何疑问，或在
9
丢弃过期的药物。
10
回到同样的药房填补药
服药时碰到任何问题，马上 联络您的医生或药剂师。
• 注意药物的适当储藏状况。 • 不要累积不需要的药物。
物，药剂师才能回顾您的 5
向医生询问新的药剂是否
资料，避免可能产生的药
会取代您正在服用的其他
物过敏或不同药物之间的
药物。
相互影响。
资料来源：新加坡国立癌症中心药房的 药物资料传单
PAGE B8
Outreach
SALUBRIS
September / October 2010
UPCOMING PUBLIC EDUCATION ACTIVITIES / PROGRAMMES
Event Name
Date, Time, Venue
Registration Details
CancerWise Workshop –
13 November 2010, Saturday
Admission fee: $5
NASOPHARYNGEAL CANCER TOPICS: a. Common nasal problems b. What is NPC? c. Causes of NPC d. How does NPC develop?
Session will be conducted in English.
To register, please call: 6225 5655 or register online: www.nccs.com.sg.
1pm – Registration 1.30pm to 4pm – Workshop Function Room, Level 4 National Cancer Centre Singapore 11 Hospital Drive, Singapore 169610
e. Risk Factors, Signs & Symptoms f. Prevention, Early Detection & Screening g. Diagnosis & Treatment h. Q&A
FOR MORE INFORMATION ABOUT CANCER Cancer Helpline Tel: 6225 5655 Email: cancerhelpline@nccs.com.sg Monday to Friday: 8.30am to 5.30pm Saturday, Sunday & Public Holiday: Closed
欲了解更多有关癌症的资讯，请拨打癌症援助热线 电话: 6225 5655 电邮: cancerhelpline@nccs.com.sg 星期一至星期五: 上午8点半至下午5点半 星期六, 星期天及公共假期: 休息
ENGAGING THE YOUNG FOR LICAM 2010
PAGE A5
Community
SALUBRIS
September / October 2010
How are you at risk of liver cancer? Have you been vaccinated against hepatitis B virus? If the answer is "No", perhaps it is time to find out more.
S
ince 2008, the National Cancer Centre Singapore has, through its Liver Cancer Awareness Month (LiCAM), relentlessly been drawing the public’s attention to the risk factors, symptoms, prevention and treatment of liver cancer. Cancer of the liver is the fourth most common and third most fatal cancer among Singaporean men, having claimed the lives of 1,507 men between 2003 and 2007, according to the Singapore Cancer Registry. The majority of patients with liver cancer do not develop any symptoms until it is too late to treat, by which time treatment options are limited. The disease is discovered often by chance when the patient is examined for other unrelated problem using imaging methods such as a Computed Tomography (CT) scan or Ultrasound (US). Risk factors for liver cancer include: • Having hepatitis B • Having cirrhosis (liver hardening) from any cause including hepatitis C, excessive alcohol consumption or obesity • Eating foods with Aflatoxin (poison from a fungus that can grow on grains and nuts that have not been stored properly)
The hepatitis B vaccination was incorporated into the national immunisation programme to protect those born in 1987 and after. The disease is commonly caused by the hepatitis virus, which causes inflammation (swelling) of the liver. Damage to the liver resulting from hepatitis will affect the liver in the long run and increase the risk of developing cancer. Individuals with hepatitis B or C are 100 times more likely to develop liver cancer than others.
“Our past efforts for liver cancer awareness targeted those born before 1987, especially the elderly. This year, we decided to engage school-going children so that they can also learn about the disease and play a part by bringing the message home to their parents and relatives,” said Professor London Lucien Ooi, Organising Chair, LiCAM 2010.
The contest kicked off in March and drew numerous well designed and meaningful entries for the three categories namely, primary school, secondary school and the junior college, preuniversity, polytechnic and ITE. Judging has concluded and the winners are: PRIMARY SCHOOL Winner
Au Wei Hoe, Fuhua Primary School
Consolations Tian Bo Lun, Fuhua Primary School Koh Wayne Gareth, Saint Andrew’s Junior School SECONDARY SCHOOL Winner
Consolations Chew Tian Wei Valerie, Dunman High School Ahmad Nazaruddin Bin Abdul Rahim, Raffles Institute TERTIARY Winner
NCCS together with Singapore General Hospital and Bayer Schering Pharma invited students to participate in its inaugural logo design contest where winners stood a chance to win attractive cash prizes.
Chong Yu Shan, Yuan Ching Secondary School
Tham May Peng Marilyn, Nanyang Polytechnic
Consolations Lim Soon Keong Allon, Singapore Polytechnic Lee Anne, Nanyang Polytechnic
By Carol Ang
PAGE A6
People
SALUBRIS
September / October 2010
LEVERAGING FROM THE BEST IN CANCER CARE
As he spoke of his stint, there were lighthearted moments that he was able to recall fondly, especially dealing with patients who were celebrities, senior politicians and billionaires. “A famous singer for whom we did a thyroidectomy gave me a private performance of “Amazing Grace”, just to prove that his voice was not affected by the surgery,” he confessed with a dry laugh.
Going to Memorial SloanKettering Cancer Center has long been a dream for Dr Gopal Iyer. And, this dream was fulfilled recently when he returned from a one-year stint from New York and to share his experience with one of the leading cancer institutions.
T
Despite having been on his feet for extended hours each day, he found time to jog down the east river with a friend on alternate days and spend his evenings catching up on research projects and writing papers. To that, he had 11 papers, six book chapters and one online course to his name.
here was every reason for Dr Gopal Iyer to lap everything up while he was in New York, a place which needs no introduction for its great offerings of art and culture. More so for an oncologist, as the Memorial Sloan-Kettering Cancer Center is one of the sought-after stops as far as cancer care and training is concerned.
The man himself had been a role model for Dr Gopal who took to his meticulous nature, obsessive traits, organizational skills and drive for perfection. “The only thing I couldn’t emulate was that he could function with only 3-4 hours of sleep. I can’t imagine giving up my sleep,” he figured.
He chanced upon the opportunity after obtaining a fellowship from the American Head and Neck Society in 2009.
The opportunity to be in the best cancer centre had come with some sacrifices such as spending more time at work. Typically, each day began at 6am, doing rounds at the wards. Then from 7am, it was off to the operating theatre till 7pm, most times alternating between surgeries and minor procedures in the ward or seeing patients needing urgent care. After 7pm, it would be post-operative ward rounds.
“It has traditionally been the Mecca for advanced head and neck surgery training. I was glad to have met Dr Jatin Shah, who is considered one of the masters of the subspecialty and was the author of numerous textbooks. I was first introduced to MSKCC as a wee third year medical student by Prof Soo Khee Chee, the director of NCCS…the fact that he was trained there as well spoke volumes about the centre.” The stint had been an eye opener in many ways. At MSKCC, he was fortunate to be in the company of some of the best medical professionals in the industry and managed to catch them in action. He had the privilege of working with Dr Jatin Shah. “Each operation done with Dr Shah was straight out of a textbook – clean, perfect, efficient and as beautiful as a painting or symphony,” he said.
It is little wonder that he chalked up over 600 surgical cases which he said was equivalent to 4-5 years’ volume and met his objective for the fellowship- to increase the number of cases under his belt, fine tune surgical skills and learn selective techniques like laser surgery for laryngeal cancers and transoral robotic surgery for pharyngeal cancers, which were new to him.
The one-year stint had been more than what he had expected when he was accorded the Michael E Burt Award by MSKCC, conferred to fellows with the best operative skills, outstanding teaching with a fine research output. With 60-70 surgical fellows contending for the award, it had come as a big surprise and as the icing on the cake. In the award presentation, Dr Shah had also cited him as “the best fellow that the centre had seen in 20 years.” The award, with its triple threads on clinical excellence, education and research had reminded him of the similarities NCCS had with MSKCC. Like Dr Gopal, many clinicians at NCCS now embark on research projects and share their expertise apart from doing clinical work. So much so that Dr Gopal finds the triple combination a big challenge. To transcend the challenge, he thinks that passion is important. “The key is to always enjoy what you are doing and be passionate about work. It is no point spending half of our waking hours of our life at a place where we don’t want to be,” said the enthusiastic Dr Gopal. Apart from clinical work, Dr Gopal is also heading the Wee Kim Wee Laboratory of Surgical Oncology and is involved research in head and neck cancers, with grants from NMRC and SingHealth.
By Veronica Lee
GIVING HOPE
PAGE A7
NCC Foundation
SALUBRIS
September / October 2010
In a bid to demonstrate their support for cancer research and the importance of hope in the patient’s healing process, five healthcare professionals and cancer survivors have offered to become ambassadors for cancer research. They are the Faces of Hope for the forthcoming charity event – Run for Hope 2010. Ms Flora Yong
G
iving hope is more than just pounding the tarmac at a charity run. The five ambassadors are going to be part of this year’s Run for Hope to encourage others to have hope and advocate the causes that they believe in, namely, importance of research in the fight against cancer.
The ambassadors are Ms Flora Yong, Mr Teo Thiam Chye, Dr Patricia Thong, Dr Gopal Iyer and Ms Tan Li Leng. For one of the ambassadors, Ms Flora Yong, was diagnosed with a benign cyst in the bladder a few years ago. Her first encounter with cancer had come early, when her father was diagnosed with cancer while she was graduating from cancer nursing school. She learnt to deal with it and as a professional, continues to wage war on the disease by conducting public education programmes for those who are affected by cancer. She also spends her free time supporting other patient causes. At the ‘Healing In Another Dimension’ Art exhibition in July 2010, she painted and donated her artwork to raise funds for patient support programmes.
Mr Teo Thiam Chye
Dr Patricia Thong
Dr Gopal Iyer
Ms Tan Li Leng
Continued on page A8.
GIVING HOPE
PAGE A8
NCC Foundation
SALUBRIS
September / October 2010
Continued from page A7.
It is heartening that healthcare professionals and cancer survivors alike, coming from different sides of the healthcare chain are united for one common cause. It goes to show that helping others in need has no boundaries.
Helping cancer patients deal with their condition was the premise why Mr Teo Thiam Chye, a programme director with a statutory board, has committed so much of his time at NCCS. Having been diagnosed with nasopharyngeal cancer in 2003 and survived the disease, he felt that it was a terrible thing for patients to struggle with the disease alone. He then became one of the pioneers who formed the NPC support group, creating a safe haven for patients and their caregivers to come together to learn and support each other. Since then the NPC group now boasts of 155 members and continues to reach out to fellow survivors and victims of the disease. Indeed, a common adage subscribed by the quintet is that each of their work has the potential of improving patients’ lives and quality of life no matter what their professions might be. In the case of Dr Patricia Thong, a research fellow at the laboratory of Optical Imaging and Photodynamic Therapy at NCCS, though she has little contact with patients, she sees her work as equally important as that of doctors and nurses as she assist doctors in giving alternative treatment to patients with no effective treatment. She is instrumental in looking for non-invasive optical methods for cancer diagnosis and therapy for oral and bladder cancers. This requires extensive research and in spite of a long wait for impactful discoveries, she feels that small results have their merits in improving the standard of medical care.
Editorial Advisors Dr Kon Oi Lian Prof Soo Khee Chee Executive Editors Ms Veronica Lee Mr Joshua Tan Mr Sunny Wee
Having a finger in every pie for cancer cure is how Dr Gopal Iyer, a Consultant with the Department of Surgical Oncology at NCCS, describes his work as a clinician and researcher. As a clinician he has found satisfaction in providing clinical care to patients, being in the frontline to treat cancer. Although Dr Gopal admits that treatment modalities may have limitations and that patients’ conditions may not improve from them, giving comfort to them could be an alternative. At the backend, he is working very hard to identify molecular pathways that can be harnessed in demolishing cancerous tumours in head and neck cancers. Sometimes, helping others offers instant gratification. Such was Li Leng’s reward whenever she spends time with cancer survivors whom she meets at dance classes. Dance and exercise are her passions and conducting classes for them was fun for her. Under the auspices of the Breast Cancer Foundation, she does this once a week and also choreographs dances whenever they have performances. As these survivors are a source of inspiration for her, Li Leng feels that doing her bit is but a mere drop of hope to alleviate their sufferings. Since five years ago, she has been paddling with three dragon boat teams of cancer survivors and has never faltered under the strenuous sport, seeing that many more fragile than her could do it as well as others. It is heartening that healthcare professionals and cancer survivors alike, coming from different sides of the healthcare chain are united for one common cause. It goes to show that helping others in need has no boundaries.
Contributing Editor Dr Wong Nan Soon
Medical Editor Dr Richard Yeo
Members, Editorial Board Ms Audrey-Anne Oei Ms Sharon Leow Ms Flora Yong
Members, Medical Editorial Board Ms Lita Chew Dr Mohd Farid Dr Melissa Teo Dr Teo Tze Hern Dr Deborah Watkinson
SALUBRIS
is produced with you in mind. If there are other topics related to cancer that you would like to read about or if you would like to provide some feedback on the articles covered, please email to salubris@nccs.com.sg.
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11 Hospital Drive Singapore 169610 Tel: (65) 6436 8000 Fax: (65) 6225 6283 www.nccs.com.sg