Applicability and usage of dose mapping/accumulation in radiotherapy

Area of Science:

• Medical Physics
• Radiation Oncology
• Radiotherapy Technology

Background:

• Dose mapping/accumulation (DMA) is a radiotherapy (RT) technique with potential for improved patient care.
• Despite years of discussion, DMA has not been widely adopted into routine clinical practice.
• Deformable image registration (DIR) is crucial for accurate DMA, but its uncertainties pose challenges.

Purpose of the Study:

• To assess the current status of DMA in RT and identify barriers to clinical implementation.
• To propose solutions and guidelines for integrating DMA and DIR into clinical workflows.
• To highlight the importance of context-driven DIR and quantified uncertainties in DMA.

Main Methods:

• Convened a working group at the ESTRO Physics workshop 2021 focused on DIR commissioning and QA for RT.
• Developed the DMA landscape (DMAL) to categorize RT use cases based on anatomical variation and dose mapping uncertainty.
• Analyzed first-order and second-order effects of DIR uncertainties on DMA, including resampling, interpolation, QA, and radiobiological considerations.

Main Results:

• The DMA landscape (DMAL) provides a framework for evaluating DMA application suitability.
• Identified key challenges in DMA, particularly second-order effects often overlooked in current literature.
• Developed recommendations for vendors and users to improve DIR and DMA integration.

Conclusions:

• Prioritize context-driven DIR over perfect DIR, considering clinical impact and uncertainties.
• Users must understand the limitations of specific DIR algorithms.
• Quantified uncertainty in dose mapping should guide decisions on whether to use mapping or not.