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Medical AI Inquiry: You was designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.  Labels: OBJECTIVE, METHODS, RESULTS. Meshes: Adult, Aged, Aged, 80 and over, Carcinoma, Non-Small-Cell Lung, Female, Fluorodeoxyglucose F18, Humans, Image Processing, Computer-Assisted, Lung Neoplasms, Male, Middle Aged, Neoplasm Staging, Positron Emission Tomography Computed Tomography, ROC Curve, Radiopharmaceuticals, Reproducibility of Results, Retrospective Studies.
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Does dual time point imaging for F18-FDG-PET/CT improve the accuracy of nodal staging in non-small cell lung cancer patients? Context: To analyze the diagnostic performance of dual time point imaging (DTPI) for pre-therapeutic lymph node (LN) staging in non-small cell lung cancer (NSCLC). This was a retrospective analysis of 47 patients with NSCLC who had undergone DTPI by PET (early + delayed) using F18-fluorodeoxyglucose (FDG). PET raw data were reconstructed iteratively (point spread function + time-of-flight). LN uptake in PET was assessed visually (four-step score) and semi-quantitatively (SUVmax, SUVmean, ratios LN/primary, LN/liver, and LN/mediastinal blood pool). DTPI analyses included retention indices (RIs), Δ-ratios and changes in visual score. Histology or cytology served as standards of reference. Accuracy was determined based on ROC analyses. Thirty-six of 155 LNs were malignant. DTPI accuracy was low for all measures (visual assessment, 24.5%; RI SUVmax, 68.4%; RI SUVmean, 65.8%; Δ-ratios, 63.9-76.1%) and significantly inferior to early PET. Accuracies of early (range, 86.5-92.9%) and delayed PET (range, 85.2-92.9%) were comparable. At early PET, accuracy of the visual score (92.9%) was similar or superior to semi-quantitative analyses (range, 86.5-92.3%).
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Using a modern PET/CT device and novel image reconstruction, neither additional delayed PET nor DTPI analyses improved the accuracy of PET-based LN staging. Dedicated visual assessment criteria performed very well. Final Decision: no