Comprehensive Commissioning and Clinical Implementation of GammaTiles STaRT for Intracranial Brain Cancer

Area of Science:

• Medical Physics
• Radiation Oncology
• Surgical Oncology

Background:

• Surgically targeted radiation therapy (STaRT) offers a novel approach for localized cancer treatment.
• GammaTiles, utilizing Cesium-131 (Cs-131) isotopes within resorbable collagen tiles, represent an advancement in brachytherapy for brain tumors.

Purpose of the Study:

• To validate the dose calculation accuracy and distribution of GammaTiles for brain tumor treatment.
• To propose a STaRT workflow for GammaTile implantation, covering planning, delivery, safety, and validation.

Main Methods:

• Dose calculations for GammaTiles were performed using MIM Symphony software and verified with hand and BrachyVision calculations.
• Two-dimensional dose distribution accuracy was validated using gafchromic EBT3 film measurements.
• A comprehensive workflow for safe and effective GammaTile implantation was established.

Main Results:

• Calculations showed good agreement, with accuracy generally below 0.5%, except for minor discrepancies in low-dose regions.
• Film measurements demonstrated good agreement (0-5%) in non-gradient areas and slightly higher differences (5-10%) in sharp dose fall-off regions.
• Minor dosimetry discrepancies were noted due to seed delineation differences between systems.

Conclusions:

• GammaTile geometry, dose distribution, and clinical workflow were comprehensively evaluated.
• Safe intraoperative implantation necessitates thorough preplanning and interdisciplinary teamwork.
• A STaRT workflow guideline was developed to aid institutions in accurate treatment planning and safe GammaTile implantation.