MSc Thesis: Advanced Optimization for Complex Radiation Therapy Treatments

RaySearch develops innovative software solutions to improve cancer care. Over 1200 clinics in more than 54 countries use RaySearch software to improve treatments and quality of life for patients. RaySearch was founded in 2000 and is listed on Nasdaq Stockholm. The headquarters is located in Stockholm, with subsidiaries in the US, Europe, Asia and Australia & New Zealand. Today we are more than 485 employees with a common vision of improving cancer care with innovative software. Our great staff is crucial for our success and we offer a fantastic working environment in modern offices, flexibility and good opportunities for development. We believe in equal opportunities, value diversity and work actively to prevent discrimination. Are you a problem-solver with a passion for mathematics, optimization, and programming? Join us in developing advanced radiation therapy solutions that could improve cancer treatment for patients worldwide.Project description This project combines mathematical optimization with software implementation within our in-house treatment planning system RayStation. The focus is photon arc therapy, the most widely used delivery technique in modern radiation therapy. In this technique, the radiation source rotates around the patient while the beam collimation, dose rate, and gantry speed are varied continuously. The aim of the project is to develop optimization methods for complex treatments of this form that take full advantage of recent advances in delivery system capabilities, with the potential to ultimately improve treatment outcomes. Optimization of photon arc treatments constitutes a large-scale nonlinear optimization problem with decision variables that govern the dose delivery, which are coupled through the mechanical limitations of the delivery system. Conventional formulations discretize these variables into control points at fixed angular intervals. The project will explore denser and nonuniform control point spacings, together with simultaneous optimization of the dose rate and gantry speed. Key questions include how to allocate control points along an arc and how to represent acceleration limits, while balancing computational cost against solution quality. The work will combine modeling, algorithm development, implementation, and evaluation on clinical cases, providing experience across the full path from mathematical formulation to implementation in an established commercial software product. AI tools will support the work, and guidance will be provided on their effective use. Your profile We are looking for an ambitious student who enjoys tackling challenging problems at the intersection of mathematics, physics and programming. We value curiosity, analytical thinking, and a willingness to learn and develop new skills. Requirements:

• Highly motivated student that has excelled in studies
• Knowledge and interest in programming
• Knowledge and interest in applied mathematics
• Excellent communication skills in Swedish and/or English

Meriting:

• Experience gained from summer/part time jobs or hobby projects
• Experience, for example through coursework, in mathematical optimization
• Programming skills in C++, C# or Python

Application Please apply to the position through the link below. Selection and interviews will be ongoing. We do not accept applications by e-mail. Application Link.