ABSTRACT
INTRODUCTION: The vulnerable atherosclerotic lesion exhibits the proliferation of neovessels and inflammation. The imaging modality 2-deoxy-2-[(18)F]fluoro-D: -glucose positron emission tomography ((18)FDG-PET) is considered for the identification of vulnerable plaques. PURPOSE: The purpose of this study was to compare the gene expression of neoangiogenesis and vulnerability-associated genes with (18)FDG uptake in patients undergoing carotid endarterectomy. PROCEDURES: Human atherosclerotic carotid artery plaques from symptomatic patients were used for gene expression analysis by quantitative PCR of vascular endothelial growth factor (VEGF) and integrin α(V) and integrin ß(3) subunits, genes essential during neoangiogenesis. We also evaluated the gene expression of CD34, a measure of microvessel density (MVD), as well as CD68, MMP-9, and cathepsin K, genes of major importance in plaque vulnerability. Gene expression analysis was compared with (18)FDG-PET. RESULTS: VEGF and integrin α(V)ß(3) gene expression did not correlate with (18)FDG uptake, whereas CD34 gene expression exhibited an inverse correlation with (18)FDG uptake. Additionally, we established that markers of vulnerability were correlated with (18)FDG uptake. CONCLUSIONS: Neoangiogenesis is not associated with (18)FDG uptake, whereas MVD and markers of vulnerability correlate with (18)FDG uptake. The absence of correlation between markers of neoangiogenesis and (18)FDG uptake suggests a temporal separation between the process of neoangiogenesis and inflammatory activity.
Subject(s)
Carotid Stenosis/metabolism , Fluorodeoxyglucose F18/pharmacokinetics , Microvessels/metabolism , Neovascularization, Pathologic/metabolism , Plaque, Atherosclerotic/metabolism , Aged , Aged, 80 and over , Antigens, CD34/genetics , Antigens, CD34/metabolism , Carotid Stenosis/diagnostic imaging , Female , Gene Expression Profiling , Humans , Integrins/genetics , Integrins/metabolism , Linear Models , Male , Microvessels/diagnostic imaging , Middle Aged , Neovascularization, Pathologic/diagnostic imaging , Plaque, Atherosclerotic/diagnostic imaging , Positron-Emission Tomography , Vascular Endothelial Growth Factor A/genetics , Vascular Endothelial Growth Factor A/metabolismABSTRACT
BACKGROUND AND STUDY AIMS: Exact staging of patients with non-small-cell lung cancer (NSCLC) is important to improve selection of resectable and curable patients for surgery. Positron emission tomography with integrated computed tomography (PET/CT) and endoscopic ultrasound guided fine needle aspiration biopsy (EUS-FNA) are new and promising methods, but indications in lung cancer staging are controversial. Only few studies have compared the 2 methods. The aim of this study was to assess and compare the diagnostic values of PET/CT and EUS-FNA for diagnosing advanced lung cancer in patients, who had both procedures performed. PATIENTS AND METHODS: 27 patients considered to be potential candidates for resection of NSCLC underwent PET/CT and EUS-FNA. Diagnoses were confirmed either by open thoracotomy, mediastinoscopy or clinical follow-up. Advanced lung cancer was defined as tumour-stage ≥ IIIA(N2), corresponding to T4- and/or N2-N3- and/or M1 disease. Diagnostic values of PET/CT and EUS-FNA, with regard to the diagnosis of advanced lung cancer, were assessed and compared. RESULTS: The sensitivity of PET/CT and EUS-FNA were respectively 60% and 60% for T4 disease, 56% versus 100% for N2-N3 disease (p=0.12) and 100% versus 33% for M1 disease (p=0.50). For diagnosing advanced lung cancer PET/CT had a sensitivity of 79%, specificity of 61%, positive predictive value (PPV) of 69%, negative predictive value (NPV) of 73%, and an accuracy of 70%. EUS-FNA had a sensitivity of 79%, specificity of 100%, PPV of 100%, NPV of 81%, and an accuracy of 89% for advanced lung cancer. CONCLUSIONS: PET/CT and EUS-FNA had a comparable sensitivity and NPV for diagnosing advanced lung cancer, but EUS-FNA had superior specificity and PPV. The two methods seem to complement each other.
