GI GEC rectal brachy dose reporting project

This study aims to identify robust dose volume and depth dose metrics for dose reporting in rectal high dose rate brachytherapy. The primary purpose of the protocol is to evaluate dosimetric parameters that are sensitive to clinically relevant variations in dose distribution while remaining stable against unavoidable delineation uncertainties, contouring variability, and differences between treatment planning systems.

The study will collect and analyze dose volume histogram based parameters from rectal brachytherapy treatment plans generated at multiple centers using different applicators and planning systems. Candidate metrics will be assessed for their ability to reflect differences between treatment plans and patients, as well as their robustness to contouring variation and dose calculation differences.

The underlying hypothesis of the study is that a limited set of dose volume metrics can be identified that consistently represent dose distribution characteristics in rectal high dose rate brachytherapy and can be reliably recorded and reported across centers. The findings of this study are expected to support the development of standardized dose reporting guidelines and facilitate improved consistency in clinical practice and future research.