Related Experiment Video
Updated: Apr 10, 2026
Dynamic Lung Tumor Tracking for Stereotactic Ablative Body Radiation Therapy
Published on: June 7, 2015
Classification and Reporting of Late Radiographic Changes After Lung Stereotactic Body Radiotherapy: Proposing a New
Hamid Raziee1, Andrew Hope1, Salman Faruqi1
1Radiation Medicine Program, Department of Radiation Oncology, Princess Margaret Cancer Center, University of Toronto, Toronto, Ontario, Canada.
Unlabelled:
Radiation-induced parenchymal lung changes after stereotactic body radiotherapy are common, and can obscure the primary tumor site. In this study we propose a structured radiographic reporting tool for characterization of these changes, pilot its feasibility in a group of radiation oncologists, and test the interrater agreement. We could demonstrate the applicability of the scale, with a fair to moderate agreement.
Background:
The purpose of the study was to design and pilot a synoptic scale for characterization of late radiographic changes after lung stereotactic body radiotherapy (SBRT).
Patients And Methods:
A participatory design process involving 6 radiation oncologists and 2 thoracic radiologists was used in the scale's design. Seventy-seven early-stage non-small-cell lung cancer patients who were treated with SBRT were included, and after treatment their serial computed tomography (CT) images were scored by 6 radiation oncologists. Gwet's First-order Agreement Coefficient (AC1) and a leave-one-out (LOO) analysis was used to assess interrater reliability and variability among raters, respectively.
Results:
The scale reports on 5 independent categories including "tumor in primary site," "tumor in involved lobe," "consolidation," "volume loss," and "ground-glass or interstitial changes." At each time point, each category is reported as "increased," "stable," "decreased," "obscured," or "not present," compared with the previous. The total number of rated images for the pilot ranged from 450 at 6 months to 84 at 48 months. The primary tumor site was scored as obscured in 38% to 40% of ratings from 12 months onward; 3% to 5% of primary tumors were scored as "increased." Consolidation, volume loss, and ground-glass or interstitial changes were increasingly marked as "stable" with time. At 24 months, AC1 was 0.28 (LOO, 0.22-0.42), 0.47 (LOO, 0.39-0.72), 0.45 (LOO, 0.42-0.50), 0.21 (LOO, 0.15-0.26), and 0.25 (LOO, 0.20-0.38) for the 5 categories listed, respectively.
Conclusion:
In a population of clinicians, this scale could be implemented to characterize evolving lung changes after SBRT, and had fair to moderate interrater agreement. Obscured tumor site is a common challenge of follow-up CT imaging, and new imaging techniques should be explored. This scale provides a tool for communicating changes after SBRT.
Related Concept Videos
01:13Radiological Investigation III: Pulmonary Angiogram and PET Scan
Pulmonary Angiogram
A Pulmonary Angiogram is an invasive procedure involving injecting a contrast medium through a catheter threaded into the pulmonary artery or the right side of the heart to visualize the pulmonary vasculature. Computed Tomography (CT) scans have mainly replaced this...
01:30Radiological Investigation II: MRI and Ventilation Perfusion Scan
Magnetic Resonance Imaging (MRI) and Ventilation Perfusion Scans are two radiological investigations that offer detailed diagnostic images of the body, particularly lung structures.
MRI
MRI uses magnetic fields and radiofrequency signals to distinguish between normal and abnormal tissues. This technology provides a more detailed diagnostic image than CT scans, enabling it to characterize pulmonary nodules, stage bronchogenic carcinoma, and evaluate inflammatory activity in...
01:30Radiological Investigation I: X-ray and CT