Initial experience in treating lung cancer with helical tomotherapy

Area of Science:

• Radiation Oncology
• Medical Imaging
• Oncology

Background:

• Helical tomotherapy integrates a linear accelerator and helical CT scanner for image-guided radiation therapy.
• Megavoltage CT (MVCT) enables real-time verification and correction of patient setup.
• Kilovoltage CT (kVCT) images are standard for treatment planning.

Purpose of the Study:

• To evaluate the utility of daily MVCT imaging in helical tomotherapy for patient setup verification and adaptive radiotherapy.
• To assess the impact of MVCT on treatment delivery accuracy in a patient with bulky non-small cell lung cancer.

Main Methods:

• A patient with Stage III bulky non-small cell lung cancer was treated using helical tomotherapy (Hi-ART II unit).
• Daily MVCT imaging was performed for patient setup verification.
• Image registration and comparison between MVCT and kVCT planning images were utilized.
• Treatment plan adaptation was considered based on significant anatomical changes detected by MVCT.

Main Results:

• Daily MVCT imaging proved effective for verifying and correcting patient setup on the treatment couch.
• MVCT imaging identified significant changes in patient anatomy during the course of treatment.
• These findings indicated the necessity for adapting the radiation delivery plan to account for anatomical variations.

Conclusions:

• Daily MVCT imaging is a valuable tool in helical tomotherapy for ensuring accurate patient positioning.
• The ability to detect and adapt to anatomical changes with MVCT supports adaptive radiotherapy strategies.
• Helical tomotherapy with daily MVCT enhances treatment precision for complex cancer cases like bulky non-small cell lung cancer.