Accuracy of Preoperative Positron Emission Tomography – Computed Tomography for Mediastinal Lymph Node Staging in Non-Small Cell Lung Cancer

Background: Accurate mediastinal lymph node staging is essential in non-small cell lung cancer (NSCLC) treatment. While 18F-fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) is widely used for noninvasive staging, its diagnostic reliability, particularly for nodal assessment, remains debated. Methods: = 252). Results: Histopathology revealed nodal metastases in 112 patients (40.3%). PET/CT detected nodal involvement with sensitivity of 66.8% and specificity of 85.2%. PPV was 50.7% and NPV 85.5%, with an overall concordance of 43.3%. Sensitivity for N1 disease was 38.2%, whereas N2 and N3 metastases were detected with sensitivities of 55.3% and 100.0%. The false-negative rate was 25.2%, with intrapulmonary nodes (station 11) most frequently missed. False-positive findings occurred in 20.1%, predominantly in hilar nodes. Multivariable analysis identified lymph node involvement and tumor stage as independent predictors of staging accuracy, whereas extracapsular extension showed a non-significant trend. Conclusion: FDG-PET/CT demonstrates high specificity and NPV but limited sensitivity for mediastinal nodal staging in NSCLC under real-world conditions. These findings are primarily driven by disease characteristics rather than methodological factors. A multimodal approach remains essential, with histopathological confirmation of PET-positive findings and selective invasive staging in PET-negative patients to ensure accurate treatment allocation.