Abstract
1886
Objectives Tc-99m EC-DG is a SPECT agent developed as an alternative to F-18 FDG for cancer imaging. Thymidine incorporation studies show intranuclear localization of EC-DG with presence in all three phases of cell proliferation. Glucose loading studies for macrophage and neutrophil uptake show minimal EC-DG uptake whereas FDG has avid uptake and competes directly with glucose A Phase 2 study was conducted to compare EC-DG SPECT/CT and FDG PET/CT for diagnosing and staging patients with non-small cell lung cancer (NSCLC).
Methods Twenty two patients with biopsy proven NSCLC were imaged with FDG PET/CT and EC-DG SPECT/CT to diagnose and stage their cancers. Standard of care protocols were used for FDG imaging. The EC-DG protocol required SPECT/CT imaging be performed three hours post injection of 1 mg EC-DG labeled with 25 mCi Tc-99m. The study included SPECT/CT systems from all three major vendors at the six sites participating in the study. The image sets were objectively assessed by independent PET and SPECT expert readers at a core lab. Assessment included location, size and confidence the detected lesions represent cancer.
Results There was 100 % concordance between EC-DG and FDG for location, size and confidence the primary lesion represented cancer. There was 90 % concordance for location, size and confidence detected lesions were metastatic.
Conclusions Objective comparative image interpretation on twenty two patients resulted in excellent concordance for both primary and metastatic lesions. The study results suggest EC-DG may provide a SPECT alternative to FDG PET imaging for diagnosing and staging patients with NSCLC.
Research Support Cellpoint LLC: Centennial Colorad