The aim of this preliminary study was to investigate the potential role of Tc-99m GSH scintigraphy in the diagnosis and staging of patients with lung cancer. Twenty five patients with newly biopsy-proven primary lung cancer were included in this study. Whole body imaging was performed at the 1st and 3rd hours after the injection of 15 mCi (555 MBq) of Tc-99m GSH. Thorax SPECT imaging was also performed at the 1st hour in all patients. SPECT and whole body imaging showed increased tracer uptake in primary lesion sites in 23 and 22 of 25 patients with lung cancer, respectively. The tumor/background activity ratios in early and late images were 1.29 to 2.35 (mean 1.74) and 1.41 to 4.03 (mean 2.01), respectively. Mediastinum could not be clearly evaluated due to high blood pool activity of Tc-99m GSH. According to the results of this study, detection rate of distant metastases with Tc-99m GSH is not adequate. As a nonspecific tumor imaging agent, Tc-99m GSH scintigraphy has not enough specificity for using in a routine fashion in lung cancer. However, it could be a promising radiopharmaceutical due to having potential to visualize in vivo GSH metabolism which is important in chemo- or radio-therapy resistance.
Keywords: Lung cancer, SPECT, staging, Tc-99m glutathione scintigraphy
