Establishment of adaptive radiotherapy by deformable image registration using planning-CT and cone-beam CT

Not Applicable

• Conditions: Head and neck cancer, prostate cancers, lung cancer, liver cancer, cervical cancer

• Registration Number: JPRN-UMIN000025273
• Lead Sponsor: Hyogo College of Medicine

Brief Summary

Deformable image registration (DIR) has been an important component in adaptive radiotherapy (ART). Our goal was to examine the accuracy of ART using the dice similarity coefficient (DSC) and to determine the optimal timing of replanning. A total of 22 patients who underwent volume modulated arc therapy (VMAT) for head and neck (H&N) cancers were prospectively analyzed. The planning target volume (PTV) was to receive a total of 70 Gy in 33 fractions. A second planning CT scan (rescan) was performed at the 15th fraction. The DSC was calculated for each structure on both CT scans. The continuous variables to predict the need for replanning were assessed. The optimal cut-off value was determined using receiver operating characteristic (ROC) curve analysis. In the correlation between body weight loss and DSC of each structure, weight loss correlated negatively with DSC of the whole face (rs = -0.45) and the face surface (rs = -0.51). Patients who required replanning tended to have experienced rapid weight loss. The threshold DSC was 0.98 and 0.60 in the whole face and the face surface, respectively. Patients who showed low DSC in the whole face and the face surface required replanning at a significantly high rate (P < 0.05 and P < 0.01). Weight loss correlated with DSC in both the whole face and the face surface (P < 0.05 and P < 0.05). The DSC values in the face predicted the need for replanning. In addition, weight loss tended to correlate with DSC. DIR during ART was found to be a useful tool for replanning.

Detailed Description

Not available

Study Timeline

• Results First Posted: 1900-01-01
• Study Start: 2016-12-15
• Study Completion: 2017-12-14
• Last Update Posted: 17 October 2023

Recruitment & Eligibility

• Status: Complete: follow-up complete
• Sex: All
• Target Recruitment: 60

Inclusion Criteria

Not provided

Exclusion Criteria

Except above condition.

Study & Design

• Study Type: Interventional
• Study Design: Not specified

Primary Outcome Measures

Name	Time	Method
This study compares dose distribution with CT and CBCT. We evaluate the clinical efficacy of this method based on these results.