An Interview with A/Prof James C L Lee
A/Prof James C L Lee, Chief Radiation Physicist (Division of Radiation Oncology, National Cancer Centre Singapore) and Adjunct Associate Professor (Department of Physics, National University of Singapore; Division of Physics & Applied Physics, School of Physical & Mathematical Sciences, College of Science, Nanyang Technological University) shares about medical physics and medical physicists at the forefront of medical treatment.
What role does medical physics or medical physicists play in modern medicine?
Medical physics is the application of physics in medicine and a medical physicist bridges the two disciplines together. More specifically, my role as a medical physicist applies the principles of radiation physics to treat cancer. For example, in radiotherapy or radiation oncology where I am trained and work in, the application of radiation physics, nuclear physics and radiation dosimetry are important to ensure that radiotherapy is being administered safely and effectively to our patients. As physicists, we work closely with medical doctors, called radiation oncologists, as well as radiation therapists and dosimetrists to provide the necessary medical physics input while they manage the medical treatment of the patients. Physics input involves, for example, radiation dose calculations, measurements and quality assurance. We all work together as a treatment team for our patients. The same applies for other related areas like nuclear medicine and radiology/diagnostic imaging. These are all medical disciplines using radiation techniques involving medical physicists.
Other important roles that medical physicists play are radiation safety, education and research. Radiation safety such as facility shielding, optimising treatment plans and imaging protocols are important contributions by medical physicists. Some medical physicists are also involved in education, for example, in the teaching of medical physics to medical residents and radiation therapy students in the university. Many medical physicists also contribute to new innovations and scientific investigations through research and academic positions at the universities.
Besides having a background knowledge in physics, what further skills or training are necessary to be a medical physicist?
Certainly a good knowledge of radiation physics, nuclear physics and related physics is important. Other related sciences like computing and mathematics are also important. Experimental physics skill is important as measurements and calibrations are an integral part of a medical physicist’s work. We are also increasingly using complex computational physics techniques like Monte Carlo simulation for radiation transport and radiobiological modelling for clinical treatment planning. Medical physicists today often write in-house programs to improve workflow, quality assurance and analyse data.
A clinically qualified medical physicist (CQMP) needs to have a good sense of safety and competence like how radiation is being clinically applied to patients for diagnosis or treatment. As medical physicists work in a clinical environment, they also need to have the soft skills to work well among physics staff and with different groups of people like the radiation oncologists, radiologists, radiation therapists and radiographers. To me, safety, competence and teamwork are all important criteria for working in a clinical environment where the ultimate benefit goes to the patients.
In a radiotherapy clinic, certain problems can be solved by physics but it may not necessarily result in a comfortable setup for the patients. Therefore, we have to be part of a multi-disciplinary team to work on designing treatment that delivers radiation dose to the tumour optimally and, if possible, comfortably for the patient who has to undergo treatment over several weeks. One example is in the treatment of a patient who is pregnant. We obviously want to shield the foetus maximally but at the same time we need to use physics to design a practical solution based on machine limitations and patient comfort in order to treat the condition optimally while minimising any risk to the foetus.
The current requirement for entry level medical physicist position is a physics degree. It is however highly recommended for medical physicists to attain either a specialised Masters in Medical Physics or related field, or a PhD in Physics, Medical Physics or related field. All medical physicists will have to undergo a further two-year Medical Physics Residency Program before being certified as a CQMP.
What scope of work is available for medical physicists in Singapore?
Internationally, most medical physicists are employed in radiotherapy. It is mandatory that medical physicists be present due to the handling of high doses of radiation and the setup precision required. There is also complex optimisation and calculations involved in treatment plans. Other important areas include machine and patient specific quality assurance, radiation dose calibration, handling of radioactive materials and radiation safety. We also have an important role to evaluate new technologies and radiation delivery techniques and to take the physics lead in implementing them in the clinic. A good example will be Proton Beam Therapy. It relies heavily on medical physicists to implement such a complex technology for clinical use.
Nuclear medicine, a small community, is another field requiring medical physicists. It involves the production and use of radioactive materials and radiotracers for mainly diagnostic purposes. If the demand for nuclear medicine expands in Singapore, more medical physicists will be required.
There is now an increasing awareness of the role of medical physicists in diagnostic imaging or radiology like CT scans and MRI. Medical physicists can contribute by optimising image quality, performing comprehensive quality assurance and ensuring radiation safety.
Some medical physicists are employed in radiation protection agency that involves licensing and policy making. Others may also be employed in hospitals as health physicists in charge of the radiation safety program.
There are also medical technology companies providing medical devices like CT, MRI and Ultrasound and special clinical software that support radiotherapy, diagnostic imaging or nuclear medicine. These companies often employ suitably trained medical physicists as application specialists and in sales.
What are some of the challenges faced by medical physicists?
The science behind radiation treatment can be rather complex. For instance, radiation dose calculation algorithm and their commissioning for clinical use. Beam commissioning of a linear accelerator is also complex and time consuming, especially for advanced radiation techniques requiring very high precision. One of the key challenges faced by medical physicists is really about being competent to practise the right physics in the light of new and challenging technologies.
Treatment in radiotherapy has gone from photons to particle therapy, from simple to complex, and from 2D to 4D in the recent decade or so. So it is going to be challenging for medical physicists. Like all new and competitive technologies, not everything is good or beneficial. We have to work with the doctors to evaluate and decide what is the right technology for our patients. It will be the medical physicists who have to learn the technology, commission it and educate the team, making sure that it runs safely.
There will be a great and diverse team of people with specialised training working together. In radiotherapy, we have to learn how to work effectively and rely on each other as a team of radiation oncologists, medical physicists, radiation therapists, dosimetrists and nurses. Working together requires effort and commitment.
Share with us your greatest job satisfaction.
Though the nature of work can be rather physics-based, I always know that we are helping patients. I take pride in taking care of patients by doing my best and making sure I am practising the best science. In everything I do, whether technical or management, my decisions are patient-centred and, if needed, for our national healthcare interest. Making sure that we are current with our physics and technology is of paramount importance to me.
I am also involved in some regional and international medical physics work via the South East Asian Federation of Organizations for Medical Physics and the International Atomic Energy Agency or IAEA. Occasionally we will organise medical physics workshops for IAEA. I am glad to be able to contribute to some form of training at the international level.
In terms of teaching, I helm an applied physics module “Medical Physics for Radiotherapy” at NTU and currently I am an adjunct faculty with the Department of Physics, NUS. I find teaching undergraduates and supervision of post-graduate students challenging but satisfying. In recent years, I have also introduced the Medical Physics Residency for Radiotherapy program at the National Cancer Centre Singapore (NCCS). I am glad to have the privilege of building up a new generation of medical physicists.
These are my job satisfaction.
Do you have any words of advice for physics graduates aspiring to be at the forefront of medicine or healthcare?
I think there are different options which graduates can consider as I have shared earlier. The most obvious is to find a medical physicist position in the public or private hospitals, preferably with a residency program. A few of my students have gone on for further studies overseas and obtained a Masters in Medical Physics. They are also clinically qualified and practicing in hospitals and medical tech companies. Others have gone on to join the regulators in government service at the National Environment Agency or as clinic executives for patient care. It is also possible to join the Ministry of Health as health and management executives. A couple of my graduates have joined the medical tech industry as application support specialists. Do carry an open mind as demand and openings may vary. The general market for healthcare personnel is expanding, so keep your options open, study them carefully and choose wisely.