OBJECTIVE: Pulmonary Kaposi's sarcoma (KS) occurs in more than 10% of patients with acquired immunodeficiency syndrome (AIDS) and has a high mortality rate. Prompt detection, diagnosis, and treatment reduce patient morbidity and mortality. The objective of this study was to determine the efficacy of 99mTc-hexakis-2-methoxy isobutyl isonitrile (99mTc-MIBI) imaging in detecting pulmonary AIDS-related KS. METHODS: 99mTc-MIBI imaging was performed on 72 human immunodeficiency virus-seropositive patients with bronchoscopic diagnosis of pulmonary KS (36 patients), pneumonia (22), normal tracheo-bronchial tree (11), lymphoma (2), and bronchogenic carcinoma (1). Lung uptake and lymph node detection in KS were compared on planar and single photon emission computed tomography (SPECT) scans. RESULTS: The lung/myocardium ratios on the 1-h planar images were significantly higher in KS and normal lungs than opportunistic infection. Using the lung/myocardium ratio of 1 as cutoff, the sensitivity, specificity, and accuracy of the 1-h planar images for detecting pulmonary KS were 75, 57.58, and 66.67%, respectively. Abnormal lymph node uptake, pleural/pericardial effusions, and ascites were detected more readily on SPECT. CONCLUSION: Planar 99mTc-MIBI imaging has moderate sensitivity, specificity, and accuracy for detecting pulmonary KS. SPECT is more effective in detecting abnormal lymph nodes, pleural/pericardial effusions, and ascites. 99mTc-MIBI SPECT followed by planar imaging at 40-60 min can be useful in assessing pulmonary KS.
OBJECTIVE:Pulmonary Kaposi's sarcoma (KS) occurs in more than 10% of patients with acquired immunodeficiency syndrome (AIDS) and has a high mortality rate. Prompt detection, diagnosis, and treatment reduce patient morbidity and mortality. The objective of this study was to determine the efficacy of 99mTc-hexakis-2-methoxy isobutyl isonitrile (99mTc-MIBI) imaging in detecting pulmonary AIDS-related KS. METHODS:99mTc-MIBI imaging was performed on 72 human immunodeficiency virus-seropositivepatients with bronchoscopic diagnosis of pulmonary KS (36 patients), pneumonia (22), normal tracheo-bronchial tree (11), lymphoma (2), and bronchogenic carcinoma (1). Lung uptake and lymph node detection in KS were compared on planar and single photon emission computed tomography (SPECT) scans. RESULTS: The lung/myocardium ratios on the 1-h planar images were significantly higher in KS and normal lungs than opportunistic infection. Using the lung/myocardium ratio of 1 as cutoff, the sensitivity, specificity, and accuracy of the 1-h planar images for detecting pulmonary KS were 75, 57.58, and 66.67%, respectively. Abnormal lymph node uptake, pleural/pericardial effusions, and ascites were detected more readily on SPECT. CONCLUSION: Planar 99mTc-MIBI imaging has moderate sensitivity, specificity, and accuracy for detecting pulmonary KS. SPECT is more effective in detecting abnormal lymph nodes, pleural/pericardial effusions, and ascites. 99mTc-MIBI SPECT followed by planar imaging at 40-60 min can be useful in assessing pulmonary KS.