Feasibility study of beam orientation class-solutions for prostate IMRT.

Area of Science:

• Radiation Oncology
• Medical Physics

Background:

• Intensity Modulated Radiation Therapy (IMRT) is widely used for prostate cancer.
• Current IMRT prostate treatment planning lacks standardized guidelines for beam orientation selection, often relying on empirical methods.
• This variability can impact treatment efficiency and consistency.

Purpose of the Study:

• To investigate interpatient variations in optimal beam configurations for prostate IMRT.
• To develop a set of standardized beam orientation class-solutions for varying numbers of incident beams.
• To facilitate more efficient and consistent IMRT prostate treatment planning.

Main Methods:

• Utilized fifteen prostate cancer cases to generate beam orientation class-solutions.
• Employed a multiobjective optimization engine to determine optimal beam directions for each patient and beam number.
• Analyzed angular distributions of optimized beams to identify and average optimal directions, creating class-solutions.
• Validated class-solutions against patient-specific optimizations on an additional clinical case.

Main Results:

• Identified specific optimal gantry angles for 3, 5, 6, 7, 8, and 9 beam configurations.
• Class-solutions for beam orientations were generated by averaging optimal directions across fifteen prostate cases.
• Validation showed clinically insignificant differences between plans using class-solutions and patient-specific optimizations.

Conclusions:

• The proposed class-solutions provide a guideline for selecting beam orientations in prostate IMRT.
• These standardized orientations can streamline the treatment planning process without compromising clinical outcomes.
• The findings support the adoption of class-solutions for more efficient and reproducible prostate IMRT planning.