Four-Dimensional Computed Tomography Ventilation Image-Guided Lung Functional Avoidance Radiation Therapy: A...

Area of Science:

• Radiation Oncology
• Medical Imaging
• Pulmonary Medicine

Background:

• Lung cancer treatment often involves radiation therapy (RT) that can affect healthy lung tissue.
• 4-dimensional computed tomography (4D-CT) provides functional information about lung ventilation.
• Assessing the safety and feasibility of integrating ventilation imaging into RT planning is crucial for improving patient outcomes.

Purpose of the Study:

• To evaluate the safety and feasibility of lung functional avoidance radiation therapy (RT) guided by 4-dimensional computed tomography (4D-CT) ventilation imaging.
• To compare radiation dose metrics between standard RT plans and functional avoidance plans.

Main Methods:

• A prospective pilot trial involving 33 evaluable lung cancer patients (24 CFRT, 9 SBRT).
• Standard 4D-CT scans were processed to generate ventilation images.
• Intensity modulated RT plans were created, comparing standard versus functional avoidance approaches.

Main Results:

• Functional avoidance RT was safely administered, with low rates of grade ≥3 pneumonitis (4.2%) and esophagitis (12.5%) in the conventionally fractionated RT (CFRT) group.
• No grade ≥3 adverse events were observed in the stereotactic body RT (SBRT) group.
• Functional avoidance plans significantly reduced radiation dose to ventilated lung regions (P < .01) without compromising target coverage.

Conclusions:

• Lung functional avoidance RT guided by 4D-CT ventilation imaging is a safe and feasible technique.
• This approach effectively reduces radiation dose to functional lung tissue.
• The findings support the clinical utility of functional avoidance RT in lung cancer management.