Prospective feasibility study of diagnostic CT-based simulation-free palliative radiotherapy

Area of Science:

• Oncology
• Radiotherapy
• Medical Imaging

Background:

• Conventional radiotherapy (RT) involves lengthy planning computed tomography (pCT) and treatment planning, delaying treatment initiation.
• Simulation-free radiotherapy (SFRT) utilizes diagnostic CT (dCT) to potentially expedite RT delivery.
• Prospective studies on SFRT in Japan are limited.

Purpose of the Study:

• To prospectively evaluate the feasibility and safety of SFRT in a Japanese clinical setting.
• To assess treatment completion rates, patient time in center, and pain response for SFRT.

Main Methods:

• A single-center, single-arm prospective study enrolled patients with vertebral metastases eligible for single 8-Gy fraction RT.
• Included dCT scans acquired within 56 days, without immobilization, and with identifiable lesions.
• Mandatory cone-beam CT (CBCT) for patient setup and verification.

Main Results:

• 100% RT completion rate in five patients (six vertebral sites).
• Mean time in center (TIC) was 45 minutes.
• Pain response observed in 25% at 4 weeks and 33% complete response at 12 weeks; no acute adverse events (AEs).

Conclusions:

• SFRT is a feasible and safe radiotherapy option for selected patients with vertebral metastases in Japan.
• The approach can be successfully implemented in community hospitals with appropriate patient selection and CBCT guidance.
• SFRT shows potential to reduce treatment delays and improve patient outcomes.