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Research Master Thesis: Optimization of radiation therapy treatment plans considering the time-dependency of the treatment delivery

We offer a master’s thesis position in optimization within the research department at our head office in central Stockholm.

The topic is to create and evaluate optimization models that take more aspects of the delivery of radiation therapy treatment plans into account than is usually done today. The end goal is to provide better chances for survival and less side effects for cancer patients receiving radiation therapy.

Your tools for this task are RaySearch’s powerful treatment planning software RayStation, the RayStation scripting interface in Python and the RayStation development code in C++ and C#. As support you will have your supervisors at RaySearch, the RaySearch crew in general and the researchers particularly.

Background and purpose

Half of Swedish cancer patients receive radiation therapy during their illness. In modern radiation therapy, the patient is irradiated with modulated fluence, which is achieved by superpositioning of radiation delivered sequentially in time through differently shaped apertures. The aperture shapes are described in a treatment plan, which is determined by mathematical optimization of the treatment plan. The optimization determines parameters such as the aperture shapes to minimize an objective function pertaining to the predicted plan quality.

The time-dependency of the delivery of the treatment is currently neglected during treatment planning. Hence, breathing motion and other changes in the patient geometry during the treatment delivery risk leading to insufficient quality of the delivered plan, and hence a reduced chance of survival for the patient. The goal of this project is to create and evaluate treatment plan optimization methods that take the time-dependency of the treatment delivery into account.

The specific objectives are:

  • To develop and evaluate methods for taking the time-dependency of the treatment delivery into account during the treatment plan optimization.
  • To develop robust optimization methods to take the uncertainty in the time-structure of the treatment delivery into account during the optimization.
  • To investigate methods to utilize the degrees of freedom available in modern treatment machines to mitigate adverse effects of the time-dependency of the treatment delivery.
  • To evaluate the proposed methods with respect to plan quality, optimization time, delivery time and robustness.
  • To implement a method in a research version of RaySearch’s commercial treatment planning system RayStation®.

Education, experience and knowledge

This master’s thesis project is suitable for degrees in applied and computational mathematics, engineering physics, computer science, or similar programs where you have excelled.

You are motivated and intelligent and you like math and programming. You are used to computers and programming, if the experience is less this is compensated by will and skill to learn.

Meriting but by no means required are proven skills in C++/MATLAB/Python, less likely but still meriting is knowledge of C#/.NET.

Experience in optimization techniques is an advantage.

Spoken and written English is required, Swedish is highly meriting. 

Personal profile

You have good analytical skills and a problem-solving mindset. When working on a problem, you formulate the right questions, identify what is important and work in a goal-oriented way towards a solution. You are a strong team player who takes responsibility and contributes to a positive atmosphere. You take pride in delivering high-quality results with efficiency. 

About the research department at RaySearch

One of the responsibilities of the research department is to take brilliant ideas on how to advance radiotherapy planning and turn them into software prototypes. Promising prototypes are then further refined by the development department to be parts of our advanced software for radiotherapy planning. The research department is also involved in several research collaborations with clinical cancer centers all over the world.

Working at RaySearch

RaySearch believes in investing in its people. We prioritize knowledge-sharing, creativity and collaboration, and you will work together with some of the most talented and highly educated people in the industry. We also have a strong social culture, with regular events and activities for employees. You will work in a modern office environment, with access to the latest hardware and tools. RaySearch is committed to equal opportunities. We value diversity and are dedicated to preventing discrimination. Read more about RaySearch.

Apply for this vacant position 

You are welcome to send your application (preferably in Swedish but English is also fine) by clicking on the button below. It should include a résumé, a personal letter and documentation of your university education (BSc and MSc). Mark the application “Optimization Master Thesis 2018”.  

The recruitment process will be ongoing while this posting is present. To enquire about the status of your application, please email work@raysearchlabs.com