Mr Lim Sheng An

Radiation Therapist, National Cancer Centre Singapore &
Resident of the SingHealth Medical Dosimetry Residency Programme (2021)  


Lim Sheng An is a Radiation Therapist at National Cancer Centre Singapore (NCCS) and he is one of the first few residents to join the newly-introduced Medical Dosimetry Residency Programme in March 2021.

After five years into his career in radiotherapy at NCCS, Sheng An decided to pursue a career in medical dosimetry as he was intrigued by the highly challenging yet rewarding nature of this selected career path. After much planning and discussion with his superiors, he decided to embark on a two-year residency programme in medical dosimetry to further broaden his knowledge and capabilities in this area. We speak to Sheng An to find out more on his experience as a pioneer resident in this residency programme.

  1. Could you tell us more on what medical dosimetry is and how it is pertinent in patient care?

    A medical dosimetrist is a member of the radiation oncology team who works closely in collaboration with other radiation therapists, medical physicists, and radiation oncologists. With their expertise in radiobiology, physiology, anatomy, physics, and math, medical dosimetrists devise the most optimal radiotherapy plan with the aim to maximise radiation dose to the cancerous tumours while minimising radiation dose to other organs, thereby reducing potential side effects during the course of treatment for patients.

  2. What were your main reasons for taking up residency in medical dosimetry?

    Residency is a formalised and structured programme which allows learning in a systematic and consistent approach. It also provides opportunities for me to further build on my competency and hone my skills necessary to devise more complex radiotherapy plans. In addition, the residency programme includes formal lectures conducted by radiation oncologists and fellow colleagues, which provides me with crucial knowledge about their clinical experiences.  

  3. How does the residency training programme look like? The training can be divided into three parts:
    • Clinical knowledge - where training is provided by clinicians, including radiation oncologist,
    • Dosimetry knowledge - where training is mainly conducted by my senior colleagues, and
    • Practical sessions - where new skills are learnt through hands-on practice.

    I spent most of my time in the practical component, where my preceptor and I will aim to meet once a week. There are also exams conducted periodically to assess my clinical and dosimetry knowledge.

  4. What are some of the challenges you faced as a resident and how do you cope with them?

    The greatest challenge would be having to juggle between routine clinical work and training. Appropriate time management and prioritisation of tasks are equally important as well. My preceptors allow me to manage my own time and provide me with the flexibility to arrange our meetings. I will typically assess my clinical workload for the day in the morning to identify potential time slots for training. Breaking down complex trainings into smaller and more manageable tasks also allows me to better optimise my learning experience.

  5. What is your advice to fellow colleagues/juniors who are uncertain about entering into residency?

    The residency programme is well designed and offers a holistic training to those who aspire to be competent medical dosimetrists. I encourage interested colleagues to start thinking and planning ahead of time and embark on it as soon as they are ready.


This interview is part of a series to introduce the SingHealth Allied Health Residency Programmes and is facilitated by the SingHealth Allied Health Residency Steering Committee and SingHealth Academy College of Allied Health (CAH).


Additional Information:

Requirements for enrolment into Medical Dosimetry Residency Programme:

  • A fully registered Radiation Therapist under the Allied Health Professional Act in Singapore and holds a current license to practice radiation therapy in Singapore
  • Holds a BSc in Radiation Therapy or related discipline
  • Has at least 2 years of working experience in radiation therapy
  • Completed at least 6 months’ rotation in basic treatment planning prior to application
  • Application with good recommendation letter