Dr Ang Peng Tiam, Medical Director at Parkway Cancer Centre, and Dr Teoh Tiong Ann, Colorectal Surgeon at Teoh Colon Rectum and General Surgery, take common questions about cancer and its causes.
What is cancer and how does it start?
Dr Ang: Cancer is a growth in the body. Besides just growing and invading, it can spread. That’s the frightening part. If you have a tumour that stays in one place, it’s not really very dangerous. But if you have a tumour that destroys the neighbouring structures, spread and attack other parts of the body, then it becomes life-threatening.
What is the difference between normal cells and cancer cells?
Dr Ang: Normal cells grow in an organised manner and every day, new cells replace old ones in a normal regenerative process. Cancer cells grow in a disorganised manner and without regard for its neighbouring structures. It has the capability of eating into adjacent areas. It can migrate or spread to other parts of the body.
What causes cancer?
Dr Ang: In some cancers, we don’t even know the reason. But for others, we have a clear idea of what happens.
In lung cancer, the No. 1 cause among a large majority of male patients is cigarette smoke. This contains carcinogen which destroys normal lung tissue and in the regenerative process, some abnormal cells will form and these abnormal cells have the ability to mutate and transform into cancer cells. In other cancers, like liver cancer, up to 90 per cent of all liver cancer patients either have Hepatitis B or C.
Dr Teoh: All our cells grow in an orderly fashion, they follow rules. Cancer cells don’t follow rules. And they release the inhibitors which allow the cancer cells to do whatever they want.
Is it genetic or caused by our way of living?
Dr Ang: The large majority of cancer patients may not even have a family history of cancer. So definitely, we cannot say it’s genetic or hereditary and this is very important, because a lot of people with symptoms will say they cannot have cancer because there is no family history. That’s not true. It’s very important to get rid of this misconception. But there is a genetic predisposition. If you have no family history of breast cancer, you still can get breast cancer. But if your mother and sister had breast cancer, your risk of getting breast cancer is increased.
Dr Teoh: There’s a difference between hereditary and genetic.
Hereditary means parents have the disease and are passed on to the child. What we have realised is that you may have the genes, but your parents may not have the disease. So you have a combination of genes which make you predisposed to having cancer. So it’s not just the hereditary element. And we believe that most cancers have a genetic element, but not necessarily all are hereditary.
And then the environment – the food, the pollution, the exercise, the smoking – all these make a difference too.
The number of people with cancer is rising. Is it the way we eat or live?
Dr Ang: If a country is underdeveloped, the incidents of cancer are lower. But as a country becomes more affluent, the incidence of cancer goes up. In India, the incidences of breast cancer and colon cancer are very low. But, when you look at America, the risk of invasive breast cancer is one in eight women. We believe it’s related to environmental factors – diet, pollution, stress, obesity, etc.. So we need to address these if we want to bring the numbers down.
How is it diagnosed? Does early detection help?
Dr Ang: Cancer patients are diagnosed in two ways – those who present symptoms and those who don’t. You have a persistent cough or blood in your stools and see a doctor; do some tests, and the cancer is discovered.
The second group – those with no symptoms and feeling perfectly well and the cancer is discovered during their annual check-up. Obviously, patients with symptoms tend to be diagnosed later. Those who accidentally found the cancer may still be in the earlier stages. Regardless of what cancer you are talking about, the earlier you diagnose it, the better the chances of a cure.
Dr Teoh: The problem is that a lot of people have the perception that cancer is painful. So if I don’t have pain, then I don’t have cancer. Another thing is that most symptoms of cancer like coughing or blood in the stool are very common symptoms. So that’s why a lot of people ignore the symptoms. But if the symptoms persist, you should definitely see a doctor.
What happens if the cancer cells have spread?
Dr Ang: That’s bad news. When the cancer is confined to its original location, that’s a localised cancer and a good option is to remove it surgically. But, once the cancer has spread, then you need to treat it with chemotherapy and so on.
How do you treat cancer at different stages? Is it always the same?
Dr Teoh: Every cancer is treated differently and even the stages of cancer makes a difference in the treatment. Some cancers are treated with chemotherapy, others are better treated with surgery. Many cancers are treated with combined treatments so that’s why it’s very important that you see specialists who work together in a team – the surgeon, the medical oncologist, the radiation oncologist – where they tailor the best treatment for you.
Dr Ang: I think every cancer patient deserves to have the best multi-disciplinary care. It’s very important that when a person has cancer, he must go to a centre where the doctors work together as a team. You must have the best pathologist to look at the specimen to say it is this type of cancer. With this information, we see what the preferred treatment option is. The radiologist and surgeon will assess if radiation, chemotherapy or surgery will work better, and which do you do first.
Patients should always ask – do I need the surgery, do I need the chemotherapy, do I need the radiotherapy? And what is the best sequence of that treatment?
What are the main reasons patients often present with advanced disease?
Dr Ang: Out of every 10 new cancer patients I see, seven would have advanced cancer, either with Stage 3 or 4 cancer.
Cancer in its early stages has no symptoms. It’s painless and you won’t even know it’s there. The second reason is the symptoms are not specific so people always say it is not cancer. The third reason is denial. A fourth reason is that sometimes people think cancer is incurable, so no point seeing a doctor. But it’s not true. If cancer is diagnosed early, there’s a good chance of curing it.
Is there a correlation between stress and cancer?
Dr Ang: Yes I believe there is. I cannot prove it but when patients come back due to a recurrence of the cancer, they always say they have been very stressed lately. I believe stress has a very big part to play. So if you want to stay healthy, it’s not just about physical health but mental and spiritual health as well.
People with cancer always ask ‘why me?’ How do you deal with this question from a patient?
Dr Teoh: There are some who are in complete denial. Yet, there are those who come in and ask me to just tell them what they need to do and how to do it to beat the disease. As a doctor, I manage each and every patient differently.
Dr Ang: Cancer is not what it used to be. In the past, getting cancer meant the end of the world. But nowadays, there are many patients who are very stoic, very well educated. They know it’s a serious problem, but they know there are solutions and it can be beaten. The faster patients can get over the ‘why me’ and ask: “What do I need to do to beat this?”, the better.
What is your advice on preventing cancer?
Dr Teoh: I think there’s no real way to prevent cancer but we should be aware of what is commonly known in terms of going for screening. It is important to eat moderately, do things moderately and exercise. Quit smoking as smoking increases the chance of not only cancer but many other medical problems.
Dr Ang: Eat everything in moderation, follow a healthy diet, exercise regularly, do not smoke. Also, try to detect cancer early. Go for screening – mammograms for women above 40, colonoscopy screening for men and women after turning 50, Pap smear for sexually-active women. Also, be aware of your own body. If you have persistent symptoms, don’t ignore them and get them checked. Cancer is not a death sentence. There is a high chance of curing cancer if it is diagnosed early.
Written by Ben Tan
Based on a radio interview with 94.7 UFM in Jakarta, Indonesia.
Tags: cancer diagnosis, carcinogen, dr teoh tiong ann, hepatitis cancer, history of cancer, localised cancer, prevent cancer, reduce cancer risk, stress and cancer