Cancer Counseling Hotline
|Vietnam||Tiếng Việt English|
Radiation oncology focuses X-rays or other types of high-energy radiation very precisely to kill cancer cells – this either cures the cancer or relieve cancer symptoms. Medical oncology has similar objectives but uses drugs to target cancer cell growth.
Radiation oncology is good for treating localised cancer and can sometimes be used as an alternative to surgery when the tumour cannot be safely operated on, such as when it is too big, or inaccessible, or when there is a desire to preserve a functioning organ such as the voice box or anus. In contrast, medical oncology drugs are carried in the blood stream around the body and are useful for treating cancer that has spread.
I have always been a bit of a techie. When I was still in school back in the 1980s and 1990s, the personal computer was just entering the public consciousness. I used to spend hours programming with my friends instead of studying, much to the chagrin of my parents. One time, my mother had to take away the power cord!
Physics too was a subject that came easily for me and I used to read beyond the school curriculum.
Meanwhile, I was also inspired by my father, Dr Lee Siew Khow. Every year, he would get “thank you” cards and gifts. My ambition thus was either to be a doctor, an engineer, or a computer programmer.
My father was a lung specialist and he was not very interested in my going into radiation oncology. Back in the 1990s, it was a backwater of medicine. At the time, cardiology was hot.
We had no exposure in medical school to radiation oncology. It was only when I was at the Singapore General Hospital that I stumbled on it when one of my patients needed radiation oncology.
I found it a marriage of technology and medicine, where my interests in physics and computer technology could be applied to medical treatment.
I completed specialist training in 2005, after having spent time at Singapore’s National Cancer Centre and the Royal Marsden Hospital in London. I joined Parkway Cancer Centre in 2012.
My typical day at work starts at 8.30 am and ends around 6 pm, but this can extend to 9 pm or 10 pm during busy periods.
I spend 60 per cent of my time in the clinic or the wards attending to patients. About 30 per cent of the time is spent on radiotherapy computer planning and another 10 per cent of the time is spent on other activities such as tumour boards (combined meetings with surgeons, medical oncologists and radiologists to discuss treatment of difficult cases) and other administrative matters.
First I look through scans so I can see what needs to be treated. Then I have to decide on the dose, and consider the side effects and the chances of success. I then explain all this to the patient.
I explain to the patient how the radiation therapy is done, and how the patient should take care of himself, both before and after treatment.
The next visit is the radiation preparation. The patient is immobilised and a CT scan is done. The immobilisation is important because we need an accurate and reproducible position of the area to be treated.
We need to locate the tumour and the critical normal organs. That takes about half an hour. Then over the next one to four days, I will be doing the computer planning. A simple case can be done in an hour, while a complex case could take a few days. Tumours in the head and neck tend to be more challenging, especially if the tumour is starting to grow close to nerves of the eye and brain.
The computer does most of the heavy lifting by doing the initial plan, but this has to be tweaked manually. What I do is change the different variables to make the beam more precise. Fortunately, technology has advanced and this has helped to speed things up. In 2001, the computer would take all night to generate a plan. Now, it can generate a plan in minutes.
Just before the actual radiation session, a CT scan is done to fine tune the position during the session.
Radiotherapy treatments are usually delivered over multiple sessions to spare normal organs and reduce side effects. Over a few weeks, you can accumulate a large overall dose to achieve a higher cancer cure while sparing normal tissues. This also allows normal cells to recover in-between sessions.
It is especially hard if radiotherapy was given with curative intent to a ‘good’ cancer but the patient suffers a relapse.
I get hit with a sense of guilt and discouragement even if this is unjustified. I will go through a round of self-reflection, checking myself with other doctors and staff members, looking for any non-ideal factors in the radiotherapy process to see if things could have been done better, not just to assuage my feelings but also to ensure that future patients will benefit from an ever-improving process.
Usually, I find that there was no error and I just have to put it down to bad luck. It is in the nature of cancer that some patients will suffer relapses even when treated by the best centres. This is how I have to rationalise things and move on.
What keeps me going are the patients who have done well, who have been cured or relieved of their symptoms.
I recently received an email from a patient I treated four years ago. He is from Papua New Guinea. He had massive nasopharyngeal cancer; it was coming out of his eye sockets and cheeks. He did well after the treatment. The cancer resolved completely and he writes an email every year to thank me: “I am still doing well. You saved my life. God bless you.”
I just saw an Indonesian teenager whose brain tumour I had treated four years ago. He seems to be cured now. One concern I had was that the treatment would affect his cognitive and hormonal development. Fortunately, he seems to be doing well in school and he is taller than his parents.
Victories like these help you emotionally overcome the losses you invariably face.
There is a long-standing belief that radiotherapy is a very damaging treatment. This belief has perhaps arisen from patients who had to undergo radiotherapy in the past using less advanced technologies.
Over the 18 years that I have been in radiation oncology, I have seen minor and major breakthroughs in more accurate or focused delivery leading to better cancer control and lower side effects.
I would like to reassure patients that we can deliver radiotherapy much better now than we did 20 to 30 years ago. And it continues to get better.
For my field, I hope that there will continue to be new or better ways to deliver radiation that result in better cancer control with fewer side effects. I hope that computer technology will reduce the time and manpower it currently takes to generate good radiotherapy plans. At the same time, I hope that the new hardware and software will stay affordable for most patients.
Written by Jimmy Yap
|POSTED IN||Up Close and Personal|
|TAGS||cancer doctor stories, radiotherapy (radiation therapy), tumours|
|READ MORE ABOUT||Head and Neck Cancer|
|PUBLISHED 01 JUNE 2018|