Lung 99mTc-MIBI scintigraphy: Impact on diagnosis of solitary pulmonary nodule

Abstract

Most of today available non-invasive procedures cannot clearly determinate between benign and malignant solitary pulmonary nodules (SPN). T e purpose of the study was to assess the possibility of using mTc labeled hexakis-2-methoxyisobutylisonitrile (99mTc-MIBI) to differentiate benign from malignant SPN. Sixty patients were included in the study if the CT scan showed indeterminate SPN. Prior to definitive diagnosis mTc-MIBI single photon emission computerized tomography (SPECT) was performed: early scan 10 minutes and delayed 60-120 minutes after the intravenous injection of 740 MBq mTc-MIBI using dual-headed Gamma camera. T e results were considered positive if there was an increased accumulation of the radiopharmaceutical in the area of the lung corresponding to the location of the lesion. T e mean nodule size ± SD measured on CT scan was 2.96 cm. Lung cancer was diagnosed in 30/60 patients (14 squamocellular, 10 adenocarcinoma, 3 large-cell and 3 microcellular lung carcinomas). Of the 30 patients with malignant lesions, 27 patients (90%) had positive mTc-MIBI scan results by qualitative assessment. Among benign lesions, 23/30 (76.7%) were negative on mTc-MIBI scan. T e size and PH report of SPN is statistically significantly influencing on mTc-MIBI accumulation in the SPN (p<0.01). The sensitivity specificity accuracy positive and negative predictive value were 90%, 76.6%, 79.4%, 88.5% and 83.3% respectively. mTc-MIBI SPECT is an inexpensive non-invasive diagnostic procedure which might be useful diagnostic modality in the evaluation of SPN. Easy availability and low cost makes mTc-MIBI SPECT an attractive method in evaluating SPN. © 2011 Association of Basic Medical Sciences of FBIH. All rights reserved.