PROSTATE CANCER (Preventive measures)

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PROSTATE CANCER:

(Preventive measures): 2.

Dr Lily Neo asked the Minister for Health, in view of the fact that prostate cancer is on the increase and 50% of deaths are due to late diagnosis, what is his Ministry's plan to prevent deaths due to prostate cancer.

Dr Balaji Sadasivan (for the Minister for Health): Prostate cancer is the fifth most frequent cancer among Singapore men. Its incidence rate has increased from four per 100,000 population per year during the 1968 to 1972 period to the current incidence rate of 17. One key reason is that Singapore men are now living longer. Nevertheless, our rate is low compared to other developed countries.

In 2003, prostate cancer accounted for less than 1% (0.8%) of all male deaths in Singapore. 94% of these deaths were in men above the age of 65.

The treatment for prostate cancer has improved significantly over the years. A local study has shown that the five-year relative survival from prostate cancer has improved from 39% in the 1968 to 1972 period to 57% in the 1988 to 1992 period.

Although it has been suggested that Prostate Specific Antigen (PSA) screening for prostate cancer can result in early diagnosis of the cancer, there is no conclusive scientific evidence that

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population-wide PSA screening can reduce prostate cancer mortality.

Dr Lily Neo: Could I ask the Senior Minister of State whether PSA is not the best method for early screening of prostate cancer? Therefore, could MOH consider targeted community screening, subsidising PSA test at $5 each in line with the initiative done by the Singapore Prostate Association during the prostate awareness week for men above 50 years of age with symptoms such as frequency of urine, incomplete emptying of bladder and also with a family history of prostate cancer?

Dr Balaji Sadasivan: The answer to the first question is no. There are no studies that show that population-based screening for PSA improves the outcome. If anyone has such scientific studies, they can submit it to MOH. If there is no scientific evidence that the outcome will be improved, then it is not a question of whether it is $5 or whatever price the test may be. The problem with screening with PSA is that there is a high false positive rate. So while you may pick up more patients with so-called "prostate cancer", many of them will not have aggressive prostate cancer and as a result, there will be people who are treated aggressively for a disease when the disease itself may have a benign outcome. And, hence, we may do more harm than good by doing a population-based PSA screening regime. Because there are no scientific studies that support it, we have not proceeded with that.

Mr Leong Horn Kee (Bishan-Toa Payoh): Mr Speaker, Sir, I thought that for this question, a male Member should be more interested than a female Member, especially for aged male Members. May I ask the Senior Minister of State whether it is not true that there is a higher incidence of prostate cancer in the older age group,

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ie, those in their 60s and 70s? Maybe the Minister can consider encouraging wider diagnosis and examination for the older age group and therefore allow them to use some funding, for example, from Medisave, for this kind of test.

Dr Balaji Sadasivan: Again, I would like to point out that the issue is not an issue of cost. The issue is: should screening be done on a normal population? The reason why it is not done is that large numbers of people, once they reach a certain age, will have cells in their prostate that one would consider prostate cancer. As a result, you may have a raised PSA. But it does not result in clinical disease and the life expectancy of these people is not reduced. So when you do screening, you may pick up people with essentially a benign disease. But because you have now diagnosed them as prostate cancer, you then subject them to treatment and the results of your treatment regime may be worse than if you had left them alone. That is why we should not proceed unless there are scientific studies to support it. If there is any physician who has scientific studies, the right thing to do would be to submit his or her scientific studies to the necessary experts and if the experts present to MOH a scientific case for doing that, then we will do it.

Dr Lily Neo: Mr Speaker, Sir, can I differ in opinion with the Senior Minister of State because actually, prostate cancer is the fifth most frequent cancer in Singapore presently and its incidence is increasing at 5.6% annually? And we all know that early detection can save lives. Therefore, do we not want to save people and will not the Ministry provide better detection and, at least, increase awareness amongst the public with regard to prevention and deaths from prostate cancer?

Dr Balaji Sadasivan: Mr Speaker, Sir, we all want to save lives. So we are all on the same side. But the important thing

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is that whatever we do, there must be scientific evidence. And if you have scientific evidence that a population-based screening system reduces mortality, the right thing to do is to collect that scientific evidence and send it to the Academy of Medicine, the chapter of urologists, who are the experts in that field and if they advise us that we should consider it, we will.

Mr Leong Horn Kee: Sir, I have two questions for the Senior Minister of State. First, I am not a medical doctor but I would like to ask him: if a case is being detected as a possibility of prostate cancer, could it be further tested whether the case is benign or malignant? That being the case, if it is benign, we do not treat the person but, if it is malignant, then we will treat him. Why should we treat a person if he is tested benign?

The other question I want to ask is: should not the Ministry of Health go into studies on the incidence of prostate cancer since it is the fifth most frequent cancer in Singapore?

Dr Balaji Sadasivan: Mr Speaker, Sir, therein lies the problem. If a person has PSA positive or slightly raised, then we have to decide whether the person has benign disease or malignant disease. So the person will then be subjected to a biopsy, because there is no point in doing a PSA if you are going to have a result and not do anything about it.

The biopsy itself carries a certain amount of risk because it is an invasive procedure, and people have had complications from the biopsy. A biopsy samples only a small part of the prostate, and not the entire prostate. So if your biopsy is positive, you are going into one category. If your biopsy is negative, it does not mean that you may not have prostate cancer. Then you come to the question: if you did see so-called malignant cells in your biopsy, does this

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mean that this is going to be the type of prostate cancer that is going to matastise and reduce your life expectancy? Or is this going to be the changes that we see where it does look malignant but, clinically, its cause is benign and therefore your life expectancy is not going to be affected by it, and surgical intervention or treatment may actually do you more harm? So these are all the considerations in terms of treating prostate and these are all the problems with population-based screening.

Prostate cancer is not unique to Singapore. There are many countries with a rate of prostate cancer that is much higher than Singapore. And the experts in these countries have looked at the data and none of them have advocated a nation-wide screening test. So, if there are individuals who strongly believe in it, the approach should be to garner the scientific evidence, submit it to the experts, and the experts are the chapter of urologists in the Academy of Medicine and let them evaluate. Because, really, it is not something that we here are the experts who can evaluate and tell you, yes, you are right and our specialists are wrong. But if you have such evidence, please send it to the Academy.

Mr Speaker: I think we have had enough of prostates! Dr Neo, last question, please.

Dr Lily Neo: Sir, may I suggest to the Senior Minister of State that, in fact, we do not need to do invasive biopsy as a second line after having prostate PSA, where we can do non-invasive test like ultrasound of the prostate to check whether the patient has really prostate cancer or not?

The other thing is: should we always wait for other countries to do the screening rather than do our own? Because we have a smaller population

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base and we have a better medical system here that we can do things that other countries may not be able to do.

Dr Balaji Sadasivan: When you are the first to try something, you may be the first to benefit from your initiative, but you may also be the first to suffer from the initiative. Because, as I have pointed out, as there is a high rate of false positives, you may end up treating many people for a disease that they do not have. Again, as I said, if you think that there is sufficient evidence, I would suggest that you marshall all the evidence, send it to our urologists who are the experts in this area and convince them to recommend to us that that is the right thing to do.