ABSTRACT
The aim of this study was to evaluate the role of technetium-99m methoxyisonitrile [MIBI] which is more available and cheaper than PET agents in monitoring the chemotherapeutic response in primary lung cancer. In this study, 37 patients with primary lung cancer underwent 99mTc-MIBI single photon emission tomography [SPET] before chemotherapy and after the 3rd cycle of chemotherapy. SPET images were recorded at 15 minutes [early] and at 3-4 hours [delayed] post- injection of the tracer. From the SPET images, early and delayed tumor/lung ratios [ER and DR] were obtained before and after chemotherapy. CT scan studies before and after chemotherapy were also performed for all patients. According to the changes in tumor size on CT scan taken two weeks after the 3rd cycle of the chemotherapy, patients were divided into two groups, responders [R[+]] and non- responders [R[-]]. The results suggested that 99mTc-MIBI might be used in routine practice not only to detect and evaluate active lesions, but also to predict and monitor the chemotherapeutic response in patients with primary lung cancer, especially when PET is not available