PET for mediastinal staging of lung cancer: Which SUV threshold makes sense?
261 Objectives: FDG-PET is the most accurate non-invasive staging of mediastinal lymph nodes (LN) in lung cancer. Beside visual interpretation some institutions use SUV measurements in LNs. Mostly SUV=2.5 is used as cut-off, but this choice was never deduced from respective studies. ROC analyses showed that thresholds of 4.4 or 5.8 gave highest accuracy (Vansteenkiste JCO 1998, Bryant ATS 2006). But that high SUV thresholds imply high false negative rates. The aim here was to determine an optimal SUV threshold. Methods: This study included 93 patients with suspected lung cancer which underwent mediastinoscopy/ mediastinal lymphadenectomy after FDG-PET imaging (90-150 min after 250 MBq FDG). Maximum SUV was measured in 325 LN regions biopsied afterwards. Visual interpretation used a 6 level score (— through +++). Diagnostic performance was assessed by ROC analysis. Rates of false negative (FNR) and false positive findings (FPR), the sum of both error rates (FNR+FPR) and diagnostic acc
