This pilot clinical trial studies single photon emission computed tomography (SPECT)/computed tomography (CT) in measuring lung function in patients with cancer undergoing radiation therapy. Diagnostic procedures that measure lung function may help doctors find healthy lung tissue and allow them to plan better treatment.
PRIMARY OBJECTIVES: I. To utilize SPECT/CT imaging with technetium Tc-99m microaggregated albumin (99mTc-MAA) and 99mTc-diethylenetriamine pentaacetic acid (99mTc-DTPA) to identify functional lung on serial imaging in patients receiving radiation treatment to the thorax, as well as to characterize reproducibility of perfusion and ventilation in non-irradiated lung tissue. SECONDARY OBJECTIVES: I. To estimate the dose response relationship on multiple spatial scales (global lung, regional lung, lung image voxel) between radiation dose and changes in lung ventilation and perfusion, both acutely (mid-radiation treatment) and long term (3 months post-treatment), using SPECT/CT imaging with 99mTc-MAA and 99mTc-DTPA. II. To estimate the degree of radiation response in lung tissue with varying levels of function (i.e. compare radiation dose response of well ventilated and well perfused tissue against lung tissue with poor perfusion and ventilation). TERTIARY OBJECTIVES: I. To evaluate proton radiation therapy for functional lung sparing in lung cancers and other cancer in the thorax through treatment planning comparisons to conventional photon radiation therapy. II. To evaluate the feasibility of incorporating standard-of-care fludeoxyglucose F 18 (18F-FDG) positron emission tomography (PET) images into proton and photon radiotherapy planning for dose escalation to functionally viable regions of gross thoracic disease. OUTLINE: Patients undergo 99mTc-MAA and 99mTc-DTPA SPECT/CT at baseline, mid-radiation therapy (up to 1 week post-treatment), and at 3-6 months post-treatment. Patients also undergo a pre-treatment 18F FDG PET/CT scan per standard of care. After completion of study, patients are followed up periodically.
Study Type
INTERVENTIONAL
Allocation
NA
Purpose
DIAGNOSTIC
Masking
NONE
Enrollment
12
Undergo 99mTc-MAA and 99mTc-DTPA SPECT/CT mid-radiation and post-radiation
Undergo 99mTc-MAA and 99mTc-DTPA SPECT/CT
Undergo 99mTc-MAA SPECT/CT
Fred Hutchinson Cancer Research Center/University of Washington Cancer Consortium
Seattle, Washington, United States
ProCure Proton Therapy Center-Seattle
Seattle, Washington, United States
Spatial Stability of Lung Perfusion and Ventilation Over Time, as Assessed Using 99mTc-MAA SPECT/CT
Perfusion and ventilation on SPECT/CT pre-radiation, mid-radiation, and post-radiation were compared to assess stability over time. Coefficient of determination (R²) was generated based on voxel-based comparisons between scans (R²=1 means perfect reproducibility in perfusion and ventilation between scans), based on regions outside the radiation field.
Time frame: Baseline to up to 3 months post-treatment
Radiation Dose With 50% Decrease in Lung Perfusion, Assessed Using 99mTc-MAA and 99mTc-DTPA SPECT/CT
For lung tissue inside the radiation field, changes in tracer uptake at the global lung, regional lung, and lung image voxel scales (compared to baseline) will be plotted against the radiation dose at the same scales to generate multiscale radiation dose response curves. These curves will be fit to linear and sigmoid dose-response functions. Lung regions in the upper quartile and lower quartile of ventilation and perfusion will also be separated out, and separate radiation dose response curves per region will be generated. We report here the dose at which there is a 50% decrease in lung perfusion based on the above analysis.
Time frame: Baseline to up to 3 months post-treatment
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Undergo 99mTc-DTPA SPECT/CT